Method of treatment or prophylaxis inftammatory pain

ABSTRACT

A method of treatment, reversal and/or symptomatic relief of inflammatory pain, including hyperalgesia, thermal or mechanical allodynia, in vertebrate animals, particularly in human subjects, comprising administering angiotensin II receptor 2 (AT 2  receptor) antagonists is disclosed. The AT 2  receptor antagonist may be provided alone or in combination with other compounds such as those that are useful in the control of inflammatory pain.

FIELD OF THE INVENTION

This invention relates generally to compounds that are useful in theprevention and amelioration of signs and symptoms associated withinflammatory pain. More particularly, the present invention relates tothe use of angiotensin II receptor 2 (AT₂ receptor) antagonists for thetreatment, prophylaxis, reversal and/or symptomatic relief ofinflammatory pain, including hyperalgesia, thermal or mechanicalallodynia, in vertebrate animals and particularly in human subjects. TheAT₂ receptor antagonists may be provided alone or in combination withother compounds such as those that are useful in the control ofinflammatory conditions.

SEQUENCE LISTING

The Sequence Listing submitted in Computer Readable Form on Jun. 2, 2010in patent application Ser. No. 12/294,035, filed on Sep. 28, 2008, ishereby incorporated by reference.

BACKGROUND OF THE INVENTION

Generally, pain is experienced when bodily tissues are subjected tomechanical, thermal or chemical stimuli of sufficient intensity to becapable of producing tissue damage. Pain resolves when the stimulus isremoved or the injured tissue heals. However, under conditions ofinflammatory sensitization or damage to actual nerve tissue, spontaneouspain may become chronic or permanent despite apparent tissue healing.Pain may be felt in the absence of an external stimulus and the painexperienced due to stimuli may become disproportionately intense andpersistent.

Pain can take a variety of forms depending on its origin. Pain may bedescribed as being peripheral neuropathic if the initiating injuryoccurs as a result of a complete or partial transection of a nerve ortrauma to a nerve plexus. Alternatively, pain may be described as beingcentral neuropathic following a lesion to the central nervous system,such as a spinal cord injury or a cerebrovascular accident. Inflammatorypain is a form of pain that is caused by tissue injury or inflammation.Following a peripheral nerve injury, symptoms are typically experiencedin a chronic fashion, distal to the site of injury and are characterizedby hyperesthesia (enhanced sensitivity to a natural stimulus),hyperalgesia (abnormal sensitivity to a noxious stimulus), allodynia(widespread tenderness, associated with hypersensitivity to normallyinnocuous tactile stimuli), and/or spontaneous burning or shootinglancinating pain.

Inflammatory pain has a distinct etiology, as compared to other forms ofpain. After initiation of inflammation in peripheral tissues,functionally specialized primary afferent nerve fiber endings callednociceptors become sensitized resulting in the development ofinflammatory pain. Examples include the pain that develops inassociation with inflammatory conditions such as arthritis, tendonitisand bursitis. Inflammatory pain may also arise from the viscera and anexample is inflammatory bowel disease. Inflammatory pain is also often acomponent of cancer pain, post-operative pain, trauma pain and burnspain.

Inflammation-induced nociceptor sensitization leads to increasedsensitivity and amplified responses so that pain may be produced bylow-intensity or normally innocuous stimuli. Further, inflammatory paininvolves neuroplastic changes at multiple levels of the nervous systemincluding the nociceptors themselves, the dorsal root ganglia (DRGs),the dorsal horn of the spinal cord and the brain (Woolf and Costigan,1999, Proc Natl Acad Sci USA 96: 7723-7730).

After initiation of inflammation, intracellular contents leak into theextracellular fluid, inflammatory cells are recruited and there isincreased production and release of a broad range of pro-nociceptive(i.e. pro-pain) molecules e.g. protons, serotonin (5HT), histamine,adenosine, adenosine triphosphate (ATP), bradykinin, prostaglandinE₂(PGE₂), nitric oxide (NO), interleukin-1 (IL-1), tumor necrosis factoralpha (TNFα), interleukin-6 (IL-6), leukemia inhibitory factor (LIF),nerve growth factor (NGF), by inflammatory and other cells. Exposure ofnociceptors to this pro-inflammatory “soup” has the potential to causesensitization so that innocuous stimuli are detected as painful(allodynia) or there is a heightened response to noxious stimuli(hyperalgesia) (Millan M J, 1999, Prog in Neurobiol 57: 1-164). This inturn initiates early post-translational changes in the nociceptorsthereby altering transduction sensitivity (peripheral sensitization)which may in turn increase C-fiber activity producing subsequentsensitization of dorsal horn neurons (central sensitization). Bothperipheral and central sensitization alter basal sensitivity to noxiousand non-noxious stimuli (Woolf and Costigan, 1999, supra; Porreca etal., 1999, Proc Natl Acad Sci USA 96: 7640-7644). Additionally, thereare other longer-lasting transcription-dependent changes in both theDRGs and the dorsal horn of the spinal cord involving the retrogradetransport of specific signaling molecules e.g. nerve growth factor(NGF), which is produced as a result of inflammation. The net result isthat inflammation results in a potentiated nociceptive signaling systemas well as a system whereby phenotypic changes in low-threshold Aβ-fiberinputs have the potential to contribute to the development ofstimulus-evoked rather than basal hypersensitivity (Woolf and Costigan,1999, supra; Neumann et al., 1996, Nature (London) 384: 360-364).

Although nociceptors are defined by their normally high threshold foractivation, lower intensity stimuli will activate sensitizednociceptors. Peripheral sensitization, which can be detected within avery short period, is thought to involve changes either in thetransducing molecules/receptors themselves or in the Na⁺ channels in thenerve terminals (Woolf and Costigan, 1999, supra). A change in thetransducer is best exemplified by the TRPV1 receptor, where repeatedheat stimuli or exposure to protons progressively augments the inwardcurrent through the TRPV1 receptor ion channel (Caterina et al., 1997,Nature (London) 389: 816-24; Tominaga et al., 1998, J Neurosci 18:10345-55). Additionally, phosphorylation of membrane-bound receptor/ionchannels may occur as many inflammatory mediators activate proteinkinases thereby increasing receptor phosphorylation. Phosphorylation ofthe peripherally located tetrodotoxin¹-resistant (TTXr) sodium channels,results in a greater sodium current in the terminal (Gold et al., 1998,J Neurosci 18: 10345-10355; England et al., 1996, J Physiol (London)495: 429-40; Gold et al., 1996, Proc Natl Acad Sci USA 93: 1108-12).These sensitizing changes occur locally in the peripheral nerveterminal, independent of any transcriptional changes that may occur inthe neuronal cell bodies located in the DRGs. ¹ Tetrodotoxin is aneurotoxin from the puffer fish

Inflammation increases peripheral levels of NGF (Woolf et al., 1994,Neuroscience 62: 327-31), a neurotrophin thought to play a key role ininducing transcriptional changes such as upregulation of TRPV1-receptorsand sensory-neuron-specific Na⁺-channels (Tate et al., 1998, NatNeurosci 1: 653-55; Okuse et al., 1997, Mol Cell Biol 10: 196-207) ininflammatory states. Although peripheral sensitization does not itselfrequire transcription, upregulated synthesis of components of the painsignaling system has the potential to amplify peripheral sensitization.After initiation of inflammation, there is a delay of many hours forupregulated expression and transport of proteins to occur (Woolf andCostigan, 1999, supra).

Central sensitization of the spinal cord results in an NMDAreceptor-sensitive increase in responsiveness to low- and high-intensitystimuli, both when applied to the site of inflammation (1° hyperalgesia)and in the contiguous non-inflamed area (2° hyperalgesia). Tactileallodynia and pin prick hyperalgesia in the zone of 2° hyperalgesia(Koltzenburg et al., 1992, Pain 51: 207-20) are characteristic NMDAreceptor-mediated features of central sensitization (Stubhaug et al.,1997, Acta Anaesthesiol Scand 41: 1124-32). A consequence ofinflammation-induced transcriptional changes in DRG neurons is that somelow-threshold Aβ fibers may acquire the neurochemical phenotype typicalof C-fibers such as synthesis and storage of substance P (Neumann etal., 1996, Nature 384: 360-364). This change in neurochemical expressiontogether with the inflammation-induced increase in neurokinin-1 (NK-1)receptors in the dorsal horn of the spinal cord (Krause et at, 1995, CanJ Physiol Pharmacol 73: 854-859) produce not only a potentiated systembut one in which the specific type of stimulus that can evoke centralsensitization has changed. Stimulus-induced hypersensitivity can thus bemediated by low-intensity Aβ inputs as well as high-intensity C-fiberinputs which manifests as progressive tactile allodynia where lighttouch produces a progressive increase in excitability of spinal cordneurons, something that would not happen in the non-inflamed state(Neumann et al., 1996, supra; Ma and Woolf, 1996, Pain 67: 97-106; Maand Woolf, 1997, NeuroReport 8, 807-810; Ma and Woolf, 1997, Eur JPharmacol 322: 165-171; Ma et al., 1998, Pain 77: 49-57).

Current methods for treating inflammatory pain have many drawbacks anddeficiencies. For example, corticosteroids, which are commonly used tosuppress destructive autoimmune processes, can result in undesirableside effects including, but not limited to, vulnerability to infection,weakening of tissues and loss of bone density leading to fractures, andocular cataract formation. Non-steroidal anti-inflammatory drugs maycause gastrointestinal disturbances including ulceration andgastrointestinal bleeding, skin rashes and urticaria and interstitialnephritis. More recently, the cardiovascular safety of the selectivecyclooxygenase-2 (COX-2) inhibitors has been raised as a potentiallyserious concern when these agents are administered chronically forperiods longer than one year.

Thus, better therapeutic strategies are required for the treatment andmanagement of inflammatory pain.

SUMMARY OF THE INVENTION

The present invention arises from the unexpected discovery that AT₂receptor antagonists are effective in the prevention or attenuation ofthe painful symptoms of inflammatory pain. Accordingly, in one aspect,the invention provides methods for the treatment or prophylaxis ofinflammatory pain, including acute and chronic inflammatory pain, in asubject by administering to the subject an effective amount of an AT₂receptor antagonist. Non limiting examples of suitable AT₂ receptorantagonists include small molecules, nucleic acids, peptides,polypeptides, peptidomimetics, carbohydrates, lipids or other organic(carbon containing) or inorganic molecules, as further described herein.

The AT₂ receptor antagonist is suitably administered in the form of acomposition comprising a pharmaceutically acceptable carrier or diluent.The composition may be administered by injection, by topical applicationor by the oral route including sustained-release modes ofadministration, over a period of time and in amounts, which areeffective to treat or prevent the symptoms of inflammatory pain. In someembodiments, the inflammatory pain results from an infection, a burn, anautoimmune disease, an inflammatory condition of the skin, muscle, orjoints, a cancer, a traumatic injury or surgery.

In accordance with the present invention, AT₂ receptor antagonists havebeen shown to prevent or attenuate the painful symptoms associated withinflammatory pain. Thus, in another aspect, the invention providesmethods for preventing or attenuating the symptoms of inflammatory painin a subject by administering to the subject an effective amount of anAT₂ receptor antagonist, which is suitably in the form of a compositioncomprising a pharmaceutically acceptable carrier and/or diluent.

In a related aspect, the invention provides methods for producinganalgesia in a subject, especially in a subject who has, or is at riskof developing, inflammatory pain. These methods generally compriseadministering to the subject an effective amount of an AT₂ receptorantagonist, which is suitably in the form of a composition comprising apharmaceutically acceptable carrier and/or diluent.

In a further aspect, the present invention contemplates the use of anAT₂ receptor antagonist in the manufacture of a medicament for producinganalgesia in a subject, especially in a subject who has, or is at riskof developing, inflammatory pain.

Any AT₂ receptor antagonist can be used in the compositions and methodsof the invention. In some embodiments, the AT₂ receptor antagonist isselected from compounds, and their pharmaceutically compatible salts,represented by the formula (I):

wherein:

-   -   R¹ and R² are independently selected from H, benzyl, substituted        benzyl, phenyl, substituted phenyl, C₁₋₆alkyl, substituted        C₁₋₆alkyl, C₃₋₆cycloalkyl, substituted C₃₋₆cycloalkyl, and        heteroaryl, providing that both R¹ and R² are not hydrogen,    -   R⁴ is selected from a carboxylate, carboxylic acid, sulfate,        phosphate, sulfonamide, phosphonamide or amide,    -   X is selected from CH, nitrogen, sulfur or oxygen with the        proviso that when X is sulfur or oxygen one of R¹ or R² is        absent,    -   Y is selected from sulfur, oxygen or N—R^(N), where R^(N) is        selected from H, C₁₋₆alkyl, substituted C₁₋₆alkyl, aryl,        substituted aryl, benzyl, substituted benzyl, C₁₋₄alkylaryl,        substituted C₁₋₄alkylaryl, OH, or NH₂,    -   G is a five or six membered, homoaromatic or unsaturated,        substituted or unsubstituted, heterocyclic ring including but        not limited to the following rings systems:

-   -   where the symbol ‘*’ indicates the bond shared between the fused        rings ‘A’ and ‘G’,    -   R⁵ is selected from H, C₁₋₆alkyl, phenyl, substituted phenyl,        substituted C₁₋₆alkoxy, or substituted C₁₋₆alkoxy,    -   R⁶ and R⁸ are independently selected from H, C₁₋₆alkyl,        substituted C₁₋₆alkyl, C₂₋₆alkoxy, substituted C₁₋₆alkoxy,        phenyl, phenyloxy, benzyl, benzyloxy, benzylamino, biphenyl,        substituted biphenyl, biphenyloxy, substituted biphenyloxy,        napthyl, substituted napthyl, provided that one of R⁶ or R⁸ is        not hydrogen, and    -   R⁷ is selected from phenyl, substituted phenyl, benzyl,        substituted benzyl, biphenyl, substituted biphenyl,        biphenylmethylene, substituted biphenylmethylene, napthyl,        substituted napthyl, naphthylmethylene, and substituted        naphthylmethylene.

In other embodiments, the AT₂ receptor antagonist is selected fromcompounds, and their pharmaceutically compatible salts, represented bythe formula (II):

wherein:

-   -   R¹ and R² are independently selected from H, phenyl, substituted        phenyl, benzyl, substituted benzyl, C₁₋₆alkyl, substituted        C₁₋₆alkyl, C₃₋₆cyloalkyl, substituted C₃₋₆cycloalkyl,        heteroaryl, and substituted heteroaryl, substituted        biphenylmethylene and saturated and unsaturated substituted        biphenylmethylene, provided that one of R¹ or R² is not        hydrogen,    -   R⁴ is selected from a carboxylate, carboxylic acid, sulfate,        phosphate, sulfonamide, phosphonamide or amide,    -   X is selected from CH, nitrogen, sulfur or oxygen with the        proviso that when X is sulfur or oxygen one of R¹ or R² is        absent, and    -   Y is selected from sulfur, oxygen or N—R^(N), where R^(N) is        selected from H, C₁₋₆alkyl, substituted C₁₋₆alkyl, aryl,        substituted aryl, benzyl, substituted benzyl, C₁₋₄alkylaryl,        substituted C₁₋₄alkylaryl, OH, or NH₂,

In still other embodiments, the AT₂ receptor antagonist is selected fromcompounds, and their pharmaceutically compatible salts, represented bythe formula (III):

wherein:

-   -   R¹, R² and R³ are independently selected from H, phenyl,        substituted phenyl, benzyl substituted benzyl, C₁₋₆alkyl,        substituted C₁₋₆alkyl, with the proviso that at least one of R¹        or R² are not hydrogen,    -   X is selected from CH, nitrogen, sulfur or oxygen with the        proviso that when X is sulfur or oxygen, one of R¹ or R² is        absent, or is aryl or heteroaryl with the proviso that both R¹        and R² are absent,    -   V is selected from CH or nitrogen atom,    -   Y is selected from sulfur, oxygen or N—R^(N), where R^(N) is        selected from H, C₁₋₆alkyl, substituted C₁₋₆alkyl, aryl,        substituted aryl, benzyl, substituted benzyl, C₁₋₄alkylaryl,        substituted C₁₋₄alkylaryl, OH, or NH₂,    -   R⁴ is selected from a carboxylate, carboxylic acid, sulfate,        phosphate, sulfonamide, phosphonamide, or amide,    -   G is a five or six membered, homoaromatic or unsaturated,        substituted or unsubstituted, heterocyclic ring including but        not limited to the following rings systems:

-   -   where the symbol ‘*’ indicates the bond shared between the fused        rings ‘A’ and ‘G’,    -   R⁵ is selected from H, C₁₋₆alkyl, phenyl, substituted phenyl,        substituted C₁₋₆alkyl, or C₁₋₆alkoxy,    -   R⁶ and R⁸ are independently selected from H, C₁₋₆alkyl,        substituted C₁₋₆alkyl C₁₋₆alkoxy, substituted, C₁₋₆alkoxy,        phenyl, phenyloxy, benzyl, benzyloxy, benzylamino, biphenyl,        substituted biphenyl, biphenyloxy, substituted biphenyloxy,        napthyl, substituted napthyl, provided that one of R⁶ or R⁸ is        not hydrogen, and    -   R⁷ is selected from phenyl, substituted phenyl, benzyl,        substituted benzyl, biphenyl, substituted biphenyl,        biphenylmethylene, substituted biphenylmethylene, napthyl,        substituted napthyl, naphthylmethylene, and substituted        naphthylmethylene.

In still other embodiments, the AT₂ receptor antagonist is selected fromcompounds, and their pharmaceutically compatible salts, represented bythe formula (IV):

wherein:

-   -   R¹⁰ is selected from H, halogen, C₁₋₆alkyl, phenyl, substituted        phenyl, substituted C₁₋₆alkyl, or C₁₋₆alkoxy,    -   R⁹ is selected from —NR¹³R¹⁴, wherein R¹³ and R¹⁴ are        independently selected from C₁₋₆alkyl, substituted C₁₋₆alkyl,        aryl, substituted aryl, benzyl, substituted benzyl,        C₁₋₄alkylaryl, substituted C₁₋₄alkylaryl, OH, or NH₂; a five or        six membered, saturated or unsaturated, substituted or        unsubstituted, carbocyclic or heterocyclic ring including but        not limited to:

-   -   V is selected from CH or a nitrogen atom,    -   Y is selected from sulfur, oxygen or N—R^(N), where R^(N) is        selected from H, C₁₋₆alkyl, substituted C₁₋₆alkyl, aryl,        substituted aryl, benzyl, substituted benzyl, C₁₋₄alkylaryl,        substituted C₁₋₄alkylaryl, OH, or NH₂,    -   G is a five or six membered homoaromatic or heterocyclic,        unsaturated, substituted ring including but not limited to the        following rings systems:

-   -   where the symbol ‘*’ indicates the bond shared between the fused        rings ‘A’ and ‘G’,    -   R⁵ is selected from C₁₋₆alkyl, phenyl, substituted phenyl,        substituted C₁₋₆alkyl, or C₁₋₆alkoxy,    -   W is selected from sulfur, oxygen or N—R^(N), where R^(N) is        selected from H, C₁₋₆alkyl, substituted C₁₋₆alkyl, aryl,        substituted aryl, benzyl, substituted benzyl, C₁₋₄alkylaryl,        substituted C₁₋₄alkylaryl, OH, or NH₂,    -   R⁶ and R⁸ are independently selected from H, C₁₋₆alkyl,        substituted C₁₋₆alkyl C₁₋₆alkoxy, substituted, C₁₋₆alkoxy,        phenyl, phenyloxy, benzyl, benzyloxy, benzylamino, biphenyl,        substituted biphenyl, biphenyloxy, substituted biphenyloxy,        napthyl, substituted napthyl, provided that one of R⁶ or R⁸ is        not hydrogen, and    -   R⁷ is selected from phenyl, substituted phenyl, benzyl,        substituted benzyl, biphenyl, substituted biphenyl,        biphenylmethylene, substituted biphenylmethylene, napthyl,        substituted napthyl, naphthylmethylene, and substituted        naphthylmethylene.

In still other embodiments, the AT₂ receptor antagonist is selected fromcompounds, and their pharmaceutically compatible salts, represented bythe formula (V):

wherein:

-   -   M is H or a halogen (fluoro, bromo, iodo, chloro),    -   R⁵ is selected from C₁₋₆alkyl, phenyl, substituted phenyl,        substituted C₁₋₆alkyl, or C₁₋₆alkoxy,    -   R¹⁶ is selected from C₁₋₆alkylamino, C₁₋₆dialkylamino,        substituted C₁₋₆alkylamino, substituted dialkylamino, arylamino,        diarylamino, substituted arylamino, substituted diarylamino,        alkylarylamino, dialkylarylamino, substituted alkylarylamino,        substituted dialkylarylamino, heteroarylamino, substituted        heteroarylamino, cycloalkylamino, dicycloalkylamino,        diheteroarylamino, alkylcarbonylamino, arylcarbonylamino,        alkylarylcarbonylamino, cycloalkylcarbonylamino, and    -   R¹⁷ is selected from C₁₋₆alkyl, substituted C₁₋₆alkyl, phenyl,        substituted phenyl, benzyl, substituted benzyl, biphenyl,        substituted biphenyl, biphenylmethylene, substituted        biphenylmethylene, naphthyl, substituted naphthyl, heteroaryl,        or substituted heteroaryl.

In further embodiments, the AT₂ receptor antagonist is selected from AT₂receptor antagonist peptides, illustrative examples of which includehexa-, hepta- and octapeptides, and their pharmaceutically compatiblesalts, represented by the formula:

R₁-R₂-R₃-R₄-R₅-R₆-Pro-R₇  (VIII)

wherein:

-   -   R₁ is absent or is selected from hydrogen, succinyl, L-aspartyl,        sarcosyl, L-seryl, succinamyl, L-propyl, glycyl, L-tyrosyl,        N_(α)-nicotinoyl-tyrosyl, or D- or L-asparagyl;    -   R₂ is selected from arginyl or N-benzoylcarbonyl arginyl;    -   R₃ is absent or valyl;    -   R₄ is absent or is selected from L-phenylalanyl or L-tyrosyl;    -   R₅ is selected from valyl, L-isoleucyl, L-alanyl or L-lysyl;    -   R₆ is selected from L-histidyl, L-isoleucyl, L-tyrosyl or        p-aminophenylalanyl; and    -   R₇ is selected from L-alanine, L-tyrosine, L- or D-leucine,        glycine, L-isoleucine or β-alanine residue.

In other embodiments, the AT₂ receptor antagonist is selected fromantigen-binding molecules that are immuno-interactive with an AT₂receptor polypeptide.

In still other embodiments, the AT₂ receptor antagonist is selected fromnucleic acid molecules that inhibit or otherwise reduce the level orfunctional activity of an expression product of an AT₂ receptor gene,illustrative examples of which include antisense molecules, ribozymesand RNAi molecules.

In yet another aspect, the invention provides methods for identifyingagents that antagonize an AT₂ receptor. These methods typically comprisecontacting a preparation with a test agent, wherein the preparationcomprises (i) a polypeptide comprising an amino acid sequencecorresponding to at least a biologically active fragment of an AT₂receptor polypeptide, or to a variant or derivative thereof; or (ii) apolynucleotide that comprises at least a portion of a genetic sequencethat regulates the expression of a gene that encodes an AT₂ receptorpolypeptide, wherein the polynucleotide is operably linked to a reportergene. A detected decrease in the level or functional activity of the AT₂receptor polypeptide, or an expression product of the reporter gene,relative to a normal or reference level or functional activity in theabsence of the test agent, indicates that the agent is an AT₂ receptorantagonist.

In some embodiments, the methods comprise contacting a first sample ofcells expressing an AT₂ receptor with an AT₂ receptor ligand andmeasuring a marker; contacting a second sample of cells expressing theAT₂ receptor with an agent and the ligand, and measuring the marker; andcomparing the marker of the first sample of cells with the marker of thesecond sample of cells. In illustrative examples, these methods measurethe levels of various markers (e.g., Zfhep expression; nitric oxidelevels or nitric oxide synthase levels) or combinations of markersassociated with the activation of the AT2 receptor or with theproliferation or differentiation of the cells. In these examples, anagent tests positive if it inhibits Zfhep expression or reduces thelevel of nitric oxide or the level or functional activity of nitricoxide synthase or the differentiation of the cells.

Still another aspect of the present invention provides methods ofproducing an agent for producing analgesia in a subject, especially in asubject who has, or is at risk of developing, inflammatory pain. Thesemethods generally comprise: testing an agent suspected of antagonizingan AT₂ receptor, as broadly described above; and synthesizing the agenton the basis that it tests positive for the antagonism. Suitably, themethod further comprises derivatising the agent, and optionallyformulating the derivatized agent with a pharmaceutically acceptablecarrier or diluent, to improve the efficacy of the agent for treating orpreventing inflammatory pain.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graphical representation showing that PD-123,319 producesdose-dependent relief of mechanical hyperalgesia in the ipsilateral(inflamed) hindpaw of the FCA-rat model of inflammatory pain whenassessed using the Paw Pressure Test involving the application ofnoxious pressure to the inflamed hindpaw. Asterisk denotes estimateddoses due to previously noted impurity of test compound.

FIG. 2 is a graphical representation showing that administration of FCAinduces mechanical hyperalgesia in the ipsilateral but not thecontralateral hindpaw of rats (n=24). *Significantly (p<0.05) differentfrom pre-FCA in the ipsilateral hindpaw.

FIG. 3 is a graphical representation showing that administration of FCAincrease paw volume in the ipsilateral hindpaw of rats, as expected.*Significantly (p<0.05) different from pre-FCA hindpaw volume.

FIG. 4 is a graphical representation showing the anti-hyperalgesic (A)and antinociceptive (B) effects of EMA500 (1-100 mg/kg), morphine (0.5mg/kg) and vehicle in FCA-rats.

FIG. 5 is a graphical representation showing the anti-hyperalgesic (A) %maximum possible reversal (B) and antinociceptive (C) effects of EMA600(1-100 mg/kg), morphine (0.5 mg/kg) and vehicle in FCA-rats

FIG. 6 is a graphical representation showing the effect of EMA500,EMA600, vehicle and morphine on the ipsilateral hindpaw volume at 3 hpost dosing, in FCA-rats.

FIG. 7 is a graphical representation illustrating a time course effect(3 h) of i.p. injections of morphine on the vocalization threshold topaw pressure in monoarthritic rats. Vocalization thresholds (expressedin gram) were measured before and after (14 days) induction ofmonoarthritis induced by an intraarticular injection of CFA just beforedrug injections and 0.25, 0.5, 0.75, 1, 1.5, 2 and 3 h after druginjection. n=10 rats in each group. *p<0.05 vs vehicle-treated group.

FIG. 8 is a graphical representation showing a time course effect (3 h)of i.p. injections of EMA300 on the vocalization threshold to pawpressure in monoarthritic rats. Vocalization thresholds (expressed ingram) were measured before and after (14 days) induction ofmonoarthritis induced by an intraarticular injection of CFA just beforedrug injection and 0.25, 0.5, 0.75, 1, 1.5, 2 and 3 h after druginjection. n=9-10 rats in each group. *p<0.05 vs vehicle-treated group.

FIG. 9 is a graphical representation illustrating a time course effect(3 h) of i.p. injections of EMA400 on the vocalization threshold to pawpressure in monoarthritic rats. Vocalization thresholds (expressed ingram) were measured before and after (14 days) induction ofmonoarthritis induced by an intraarticular injection of CFA just beforedrug injection and 0.25, 0.5, 0.75, 1, 1.5, 2 and 3 h after druginjections. n=9-10 rats in each group. *p<0.05 vs vehicle-treated group.

DETAILED DESCRIPTION OF THE INVENTION 1. Definitions

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by those of ordinary skillin the art to which the invention belongs. Although any methods andmaterials similar or equivalent to those described herein can be used inthe practice or testing of the present invention, preferred methods andmaterials are described. For the purposes of the present invention, thefollowing terms are defined below.

The articles “a” and “an” are used herein to refer to one or to morethan one (i.e. to at least one) of the grammatical object of thearticle. By way of example, “an element” means one element or more thanone element.

As used herein, the term “about” refers to a quantity, level, value,dimension, size, or amount that varies by as much as 30%, 25%, 20%, 15%or 10% to a reference quantity, level, value, dimension, size, oramount.

Unless otherwise indicated, the term “acyl” denotes a group containingthe moiety C═O (and not being a carboxylic acid, ester or amide)Preferred acyl includes C(O)—R, wherein R is hydrogen or an alkyl,alkenyl, alkynyl, aryl, heteroaryl or heterocyclyl residue, preferably aC₁₋₂₀ residue. Examples of acyl include formyl; straight chain orbranched alkanoyl such as, acetyl, propanoyl, butanoyl,2-methylpropanoyl, pentanoyl, 2,2-dimethylpropanoyl, hexanoyl,heptanoyl, octanoyl, nonanoyl, decanoyl, undecanoyl, dodecanoyl,tridecanoyl, tetradecanoyl, pentadecanoyl, hexadecanoyl, heptadecanoyl,octadecanoyl, nonadecanoyl and icosanoyl; cycloalkylcarbonyl such ascyclopropylcarbonyl cyclobutylcarbonyl, cyclopentylcarbonyl andcyclohexylcarbonyl; aroyl such as benzoyl, toluoyl and naphthoyl;aralkanoyl such as phenylalkanoyl (e.g. phenylacetyl, phenylpropanoyl,phenylbutanoyl, phenylisobutanoyl, phenylpentanoyl and phenylhexanoyl)and naphthylalkenoyl (e.g. naphthylacetyl, naphthylpropanoyl andnaphthylbutanoyl]; aralkenoyl such as phenylalkenoyl (e.g.phenylpropenoyl, phenylbutenoyl, phenylmethacryloyl, phenylpentenoyl andphenylhexenoyl and naphthylalkenoyl (e.g. naphthylpropenoyl,naphthylbutenoyl and naphthylpentenoyl); aryloxyalkanoyl such asphenoxyacetyl and phenoxypropionyl; arylthiocarbamoyl such asphenylthiocarbamoyl; arylglyoxyloyl such as phenylglyoxyloyl andnaphthylglyoxyloyl; arylsulfonyl such as phenylsulfonyl andnaphthylsulfonyl; heterocycliccarbonyl; heterocyclicalkanoyl such asthienylacetyl, thienylpropanoyl, thienylbutanoyl, thienylpentanoyl,thienylhexanoyl, thiazolylacetyl, thiadiazolylacetyl andtetrazolylacetyl; heterocyclicalkenoyl such as heterocyclicpropenoyl,heterocyclicbutenoyl, heterocyclicpentenoyl and heterocyclichexenoyl;and heterocyclicglyoxyloyl such as thiazolyglyoxyloyl andthienylglyoxyloyl.

If a number of carbon atoms is not specified, the term “alkenyl,” unlessotherwise indicated, refers to a non-aromatic hydrocarbon radical,straight, branched or cyclic, containing from 2 to 10 carbon atoms andat least one carbon to carbon double bond. Preferably one carbon tocarbon double bond is present, and up to four non-aromatic carbon-carbondouble bonds may be present. Thus, “C₂-C₆alkenyl” means an alkenylradical having from 2 to 6 carbon atoms. Alkenyl groups include, but arenot limited to, ethenyl, propenyl, butenyl, 2-methylbutenyl andcyclohexenyl. The straight, branched or cyclic portion of the alkenylgroup may contain double bonds and may be substituted if a substitutedalkenyl group is indicated.

As used herein, “alkenylene” refers to a straight, branched or cyclic,preferably straight or branched, bivalent aliphatic hydrocarbon group,preferably having from 2 to about 20 carbon atoms and at least onedouble bond, more preferably 2 to 12 carbons, even more preferably loweralkenylene. The alkenylene group is optionally substituted with one ormore “alkyl group substituents.” There may be optionally inserted alongthe alkenylene group one or more oxygen, sulfur or substituted orunsubstituted nitrogen atoms, where the nitrogen substituent is alkyl aspreviously described. Exemplary alkenylene groups include —CH═CH—CH═CH—and —CH═CH—CH₂—. The term “lower alkenylene” refers to alkenylene groupshaving 2 to 6 carbons. Preferred alkenylene groups are lower alkenylene,with alkenylene of 3 to 4 carbon atoms being particularly preferred.

The terms “alkoxy,” “alkenoxy,” “alkynoxy,” “aryloxy,” “heteroaryloxy,”“heterocyclyloxy” and “acyloxy” respectively denote alkyl, alkenyl,alkynyl aryl, heteroaryl, heterocyclyl and acyl groups as herein definedwhen linked by oxygen.

“Alkoxy,” unless otherwise indicated, represents either a cyclic ornon-cyclic alkyl group attached through an oxygen bridge. “Alkoxy”therefore encompasses the definitions of alkyl and cycloalkyl below. Forexample, alkoxy groups include but are not limited to methoxy, oxyethoxy, n-propyloxy, i-propyloxy, cyclopentyloxy and cyclohexyloxy.

As used herein, “alkyl” is intended to include both branched andstraight-chain saturated aliphatic hydrocarbon group and may have aspecified number of carbon atoms. For example, C₁-C₁₀, as in“C₁-C₁₀alkyl” is defined to include groups having 1, 2, 3, 4, 5, 6, 7,8, 9 or 10 carbons in linear or branched arrangement. For example,“C₁-C₁₀alkyl” specifically includes, but is not limited to, methyl,ethyl, n-propyl, i-propyl, n-butyl, t-butyl, i-butyl, pentyl, hexyl,heptyl, octyl, nonyl, decyl.

As used herein, “alkylene” refers to a straight, branched or cyclic,preferably straight or branched, bivalent aliphatic hydrocarbon group,preferably having from 1 to about 20 carbon atoms, more preferably 1 to12 carbons, even more preferably lower alkylene. The alkylene group isoptionally substituted with one or more “alkyl group substituents.”There may be optionally inserted along the alkylene group one or moreoxygen, sulfur or substituted or unsubstituted nitrogen atoms, where thenitrogen substituent is alkyl as previously described. Exemplaryalkylene groups include methylene (—CH₂—), ethylene (—CH₂CH₂—),propylene (—(CH₂)₃—), cyclohexylene (—C₆H₁₀—), methylenedioxy(—O—CH₂—O—) and ethylenedioxy (—O—(CH₂)₂—O—). The term “lower alkylene”refers to alkylene groups having 1 to 6 carbons. Preferred alkylenegroups are lower alkylene, with alkylene of 1 to 3 carbon atoms beingparticularly preferred.

As used herein, “alkylidene” refers to a bivalent group, such as ═CR9R0,which is attached to one atom of another group, forming a double bond.Exemplary alkylidene groups are methylidene (═CH2) and ethylidene(═CHCH₃). As used herein, “arylalkylidene” refers to an alkylidene groupin which either R9 or R0 is and aryl group. As used herein,“diarylalkylidene” refers to an alkylidene group in which R9 and R0 areboth aryl groups. “Diheteroarylalkylidene” refers to an alkylidene groupin which R9 and R0 are both heteroaryl groups.

The term “alkynyl” refers to a hydrocarbon radical straight, branched orcyclic, containing from 2 to 10 carbon atoms and at least one carbon tocarbon triple bond. Up to three carbon-carbon triple bonds may bepresent. Thus, “C₂-C₆alkynyl” means an alkynyl radical having from 2 to6 carbon atoms. Alkynyl groups include, but are not limited to, ethynyl,propynyl, butynyl, 3-methylbutynyl and so on. The straight, branched orcyclic portion of the alkynyl group may contain triple bonds and may besubstituted if a substituted alkynyl group is indicated.

In certain instances, substituents may be defined with a range ofcarbons that includes zero, such as (C₀-C₆)alkylene-aryl. If aryl istaken to be phenyl, this definition would include phenyl itself as wellas, for example, —CH₂Ph, —CH₂CH₂Ph, CH(CH₃)CH₂CH(CH₃)Ph.

As used herein, “alkynylene” refers to a straight, branched or cyclic,preferably straight or branched, bivalent aliphatic hydrocarbon group,preferably having from 2 to about 20 carbon atoms and at least onetriple bond, more preferably 2 to 12 carbons, even more preferably loweralkynylene. The alkynylene group is optionally substituted with one ormore “alkyl group substituents.” There may be optionally inserted alongthe alkynylene group one or more oxygen, sulfur or substituted orunsubstituted nitrogen atoms, where the nitrogen substituent is alkyl aspreviously described. Exemplary alkynylene groups include —C≡C—C≡C—,—C≡C— and —C≡C—CH₂—. The term “lower alkynylene” refers to alkynylenegroups having 2 to 6 carbons. Preferred alkynylene groups are loweralkynylene, with alkynylene of 3 to 4 carbon atoms being particularlypreferred.

The term “analgesia” is used herein to describe states of reduced painperception, including absence from pain sensations as well as states ofreduced or absent sensitivity to noxious stimuli. Such states of reducedor absent pain perception are induced by the administration of apain-controlling agent or agents and occur without loss ofconsciousness, as is commonly understood in the art. The term analgesiaencompasses the term “antinociception,” which is used in the art as aquantitative measure of analgesia or reduced pain sensitivity in animalmodels.

As used herein, the term “antagonist” means an agent that decreases orinhibits the biological activity of an AT₂ gene (Agtr2 gene) or anexpression product thereof including an AT₂ receptor polypeptide.

As used herein, the term “AT₂ receptor” means an angiotensin II type 2receptor (AT₂) receptor polypeptide that can bind angiotensin II and/orone or more other ligands. The term “AT₂ receptor” encompassesvertebrate homologs of AT₂ receptor family members, including, but notlimited to, mammalian, reptilian and avian homologs. Representativemammalian homologs of AT₂ receptor family members include, but are notlimited to, murine and human homologs.

By “antigen-binding molecule” is meant a molecule that has bindingaffinity for a target antigen. It will be understood that this termextends to immunoglobulins, immunoglobulin fragments andnon-immunoglobulin derived protein frameworks that exhibitantigen-binding activity.

“Antigenic or immunogenic activity” refers to the ability of apolypeptide, fragment, variant or derivative according to the inventionto produce an antigenic or immunogenic response in an animal, suitably amammal, to which it is administered, wherein the response includes theproduction of elements which specifically bind the polypeptide orfragment thereof.

As used herein, “aromatic” or “aryl” is intended to mean, unlessotherwise indicated, any stable monocyclic or bicyclic carbon ring of upto 7 atoms in each ring, wherein at least one ring is aromatic. Examplesof such aryl elements include, but are not limited to, phenyl, naphthyl,tetrahydronaphthyl, indanyl, biphenyl, phenanthryl, anthryl oracenaphthyl.

“Aralkyl” means alkyl as defined above which is substituted with an arylgroup as defined above, e.g., —CH₂phenyl, —(CH₂)₂phenyl, —(CH₂)₃phenyl,—H₂CH(CH₃)CH₂phenyl, and the like and derivatives thereof.

As used herein, “arylene” refers to a monocyclic or polycyclic,preferably monocyclic, bivalent aromatic group, preferably having from 3to about 20 carbon atoms and at least one aromatic ring, more preferably3 to 12 carbons, even more preferably lower arylene. The arylene groupis optionally substituted with one or more “alkyl group substituents.”There may be optionally inserted around the arylene group one or moreoxygen, sulfur or substituted or unsubstituted nitrogen atoms, where thenitrogen substituent is alkyl as previously described. Exemplary arylenegroups include 1,2-, 1,3- and 1,4-phenylene. The term “lower arylene”refers to arylene groups having 5 or 6 carbons. Preferred arylene groupsare lower arylene.

As used herein, “arylidene” refers to an unsaturated cyclic bivalentgroup where both points of attachment are on the same atom of the ring.Exemplary arylidene groups include, but are not limited to, quinonemethide moieties that have the formula:

where X is O, S or NR9. “Heteroarylidene” groups are arylidene groupswhere one or two, preferably two, of the atoms in the ring areheteroatoms, such as, but not limited to, O, S and N.

As used herein, the term “biological activity” means any observableeffect flowing from the interaction between an AT₂ receptor polypeptideand a ligand. Representative, but non-limiting, examples of biologicalactivity in the context of the present invention include association ofan AT₂ receptor with a ligand, including an endogenous ligand such asangiotensin II or an AT₂ receptor antagonist. The term “biologicalactivity” also encompasses both the inhibition and the induction of theexpression of an AT₂ receptor polypeptide. Further, the term “biologicalactivity” encompasses any and all effects flowing from the binding of aligand by an AT₂ receptor polypeptide.

Throughout this specification, unless the context requires otherwise,the words “comprise”, “comprises” and “comprising” will be understood toimply the inclusion of a stated step or element or group of steps orelements but not the exclusion of any other step or element or group ofsteps or elements.

By “corresponds to” or “corresponding to” is meant (a) a polynucleotidehaving a nucleotide sequence that is substantially identical orcomplementary to all or a portion of a reference polynucleotide sequenceor encoding an amino acid sequence identical to an amino acid sequencein a peptide or protein; or (b) a peptide or polypeptide having an aminoacid sequence that is substantially identical to a sequence of aminoacids in a reference peptide or protein.

The term “cycloalkenyl” means a monocyclic unsaturated hydrocarbon groupand may have a specified number of carbon atoms. For example,“cycloalkenyl” includes but is not limited to, cyclobutenyl,cyclopentenyl, 1-methylcyclopentenyl, cyclohexenyl and cyclohexadienyl.

Unless otherwise indicated, the term “cycloalkyl” or “aliphatic ring”means a monocyclic saturated aliphatic hydrocarbon group and may have aspecified number of carbon atoms. For example, “cycloalkyl” includes,but is not limited to, cyclopropyl, methyl-cyclopropyl,2,2-dimethyl-cyclobutyl, 2-ethyl-cyclopentyl, cyclohexyl.

By “derivative,” as applied to peptides and polypeptides, refers to apeptide or polypeptide that has been derived from the basic sequence bymodification, for example by conjugation or complexing with otherchemical moieties or by post-translational modification techniques aswould be understood in the art. The term “derivative” also includeswithin its scope alterations that have been made to a parent sequenceincluding additions or deletions that provide for functional equivalentmolecules.

By “effective amount”, in the context of treating or preventing acondition is meant the administration of that amount of active to anindividual in need of such treatment or prophylaxis, either in a singledose or as part of a series, that is effective for the prevention ofincurring a symptom, holding in check such symptoms, and/or treatingexisting symptoms, of that condition. The effective amount will varydepending upon the health and physical condition of the individual to betreated, the taxonomic group of individual to be treated, theformulation of the composition, the assessment of the medical situation,and other relevant factors. It is expected that the amount will fall ina relatively broad range that can be determined through routine trials.

The term “gene” as used herein refers to any and all discrete codingregions of the cell's genome, as well as associated non-coding andregulatory regions. The gene is also intended to mean the open readingframe encoding specific polypeptides, introns, and adjacent 5′ and 3′non-coding nucleotide sequences involved in the regulation ofexpression. In this regard, the gene may further comprise controlsignals such as promoters, enhancers, termination and/or polyadenylationsignals that are naturally associated with a given gene, or heterologouscontrol signals. The DNA sequences may be cDNA or genomic DNA or afragment thereof. The gene may be introduced into an appropriate vectorfor extrachromosomal maintenance or for integration into the host.

As appreciated by those of skill in the art, “halo” or “halogen” as usedherein is intended to include chloro, fluoro, bromo and iodo.

“Heteroaralkyl” group means alkyl as defined above which is substitutedwith a heteroaryl group, e.g., —CH₂pyridinyl, —(CH₂)₂pyrimidinyl,—(CH₂)₃imidazolyl, and the like, and derivatives thereof.

The term “heteroaryl” or “heteroaromatic,” as used herein, represents astable monocyclic or bicyclic ring of up to 7 atoms in each ring,wherein at least one ring is aromatic and contains from 1 to 4heteroatoms selected from the group consisting of O, N and S. Heteroarylgroups within the scope of this definition include but are not limitedto: acridinyl, carbazolyl, cinnolinyl, quinoxalinyl, pyrazolyl, indolyl,benzotriazolyl, furanyl, thienyl, benzothienyl, benzofuranyl,quinolinyl, isoquinolinyl, oxazolyl, isoxazolyl, indolyl, pyrazinyl,pyridazinyl, pyridinyl, pyrimidinyl, pyrrolyl, tetrahydroquinoline. Aswith the definition of heterocycle below, “heteroaryl” is alsounderstood to include the N-oxide derivative of any nitrogen-containingheteroaryl.

Further examples of “heteroaryl” and “heterocyclyl” include, but are notlimited to, the following: benzoimidazolyl, benzofuranyl,benzofurazanyl, benzopyrazolyl, benzotriazolyl, benzothiophenyl,benzoxazolyl, carbazolyl, carbolinyl, cinnolinyl, furanyl, imidazoyl,indolinyl, indolyl, indolazinyl, indazolyl, isobenzofuranyl, isoindolyl,isoquinolyl, isothiazolyl, isoxazolyl, naphthpyridinyl, oxadiazolyl,oxazolyl, oxazoline, isoxazoline, oxetanyl, pyranyl, pyrazinyl,pyrazolyl, pyridazinyl, pyridopyridinyl, pyridazinyl, pyridyl,pyrimidyl, pyrrolyl, quinazolinyl, quinolyl, quinoxalinyl,tetrahydropyranyl, tetrazolyl, tetrazolopyridyl, thiadiazolyl,thiazolyl, thienyl, triazolyl, azetidinyl, aziridinyl, 1,4-dioxanyl,hexahydroazepinyl, piperazinyl, piperidinyl, pyrrolidinyl, morpholinyl,thiomorpholinyl, dihydrobenzoimidazolyl, dihydrobenzofuranyl,dihydrobenzothiophenyl, dihydrobenzoxazolyl, dihydrofuranyl,dihydroimidazolyl, dihydroindolyl, dihydroisooxazolyl,dihydroisothiazolyl, dihydrooxadiazolyl, dihydrooxazolyl,dihydropyrazinyl, dihydropyrazolyl, dihydropyridinyl,dihydropyrimidinyl, dihydropyrrolyl, dihydroquinolinyl,dihydrotetrazolyl, dihydrothiadiazolyl, dihydrothiazolyl,dihydrothienyl, dihydrotriazolyl, dihydroazetidinyl,methylenedioxybenzoyl, tetrahydrofuranyl, and tetrahydrothienyl, andN-oxides thereof. Attachment of a heterocyclyl substituent can occur viaa carbon atom or via a heteroatom.

As used herein, “heteroarylene,” unless otherwise indicated, refers to abivalent monocyclic or multicyclic ring system, preferably of about 3 toabout 15 members where one or more, more preferably 1 to 3 of the atomsin the ring system is a heteroatom, that is, an element other thancarbon, for example, nitrogen, oxygen and sulfur atoms. Theheteroarylene group may be optionally substituted with one or more,preferably 1 to 3, aryl group substituents. Exemplary heteroarylenegroups include, for example, 1,4-imidazolylene.

The term “heterocycle”, “heteroaliphatic” or “heterocyclyl” as usedherein is intended to mean a 5- to 10-membered nonaromatic heterocyclecontaining from 1 to 4 heteroatoms selected from the group consisting ofO, N and S, and includes bicyclic groups.

“Heterocyclylalkyl” group means alkyl as defined above which issubstituted with a heterocycle group, e.g., —CH₂Pyrrolidin-1-yl,—(CH₂)₂piperidin-1-yl, and the like, and derivatives thereof.

“Hybridization” is used herein to denote the pairing of complementarynucleotide sequences to produce a DNA-DNA hybrid or a DNA-RNA hybrid.Complementary base sequences are those sequences that are related by thebase-pairing rules. In DNA, A pairs with T and C pairs with G. In RNA Upairs with A and C pairs with G. In this regard, the terms “match” and“mismatch” as used herein refer to the hybridization potential of pairednucleotides in complementary nucleic acid strands. Matched nucleotideshybridize efficiently, such as the classical A-T and G-C base pairmentioned above. Mismatches are other combinations of nucleotides thatdo not hybridize efficiently.

The term “hydrocarbyl” as used herein includes any radical containingcarbon and hydrogen including saturated, unsaturated, aromatic, straightor branched chain or cyclic including polycyclic groups. Hydrocarbylincludes but is not limited to C₁-C₈alkyl, C₂-C₈alkenyl, C₂-C₈alkynyl,C₃-C₁₀cycloalkyl, aryl such as phenyl and naphthyl, Ar(C₁-C₈)alkyl suchas benzyl, any of which may be optionally substituted.

By “hyperalgesia” is meant an increased response to a stimulus that isnormally painful.

Reference herein to “immuno-interactive” includes reference to anyinteraction, reaction, or other form of association between moleculesand in particular where one of the molecules is, or mimics, a componentof the immune system.

As used herein “inflammatory pain” refers to pain induced byinflammation. Such types of pain may be acute or chronic and can be dueto any number of conditions characterized by inflammation including,without limitation, burns including chemical, frictional or thermalburns, autoimmune diseases such as rheumatoid arthritis, osteoarthritisand colitis, as well as other inflammatory diseases including carditis,dermatitis, myositis, neuritis and collagen vascular diseases.

The term “oligonucleotide” as used herein refers to a polymer composedof a multiplicity of nucleotide residues (deoxyribonucleotides orribonucleotides, or related structural variants or synthetic analoguesthereof) linked via phosphodiester bonds (or related structural variantsor synthetic analogues thereof). Thus, while the term “oligonucleotide”typically refers to a nucleotide polymer in which the nucleotideresidues and linkages between them are naturally occurring, it will beunderstood that the term also includes within its scope variousanalogues including, but not restricted to, peptide nucleic acids(PNAs), phosphoramidates, phosphorothioates, methyl phosphonates,2-O-methyl ribonucleic acids, and the like. The exact size of themolecule can vary depending on the particular application. Anoligonucleotide is typically rather short in length, generally fromabout 10 to 30 nucleotide residues, but the term can refer to moleculesof any length, although the term “polynucleotide” or “nucleic acid” istypically used for large oligonucleotides.

By “operably linked” is meant that transcriptional and translationalregulatory polynucleotides are positioned relative to apolypeptide-encoding polynucleotide in such a manner that thepolynucleotide is transcribed and the polypeptide is translated.

The term “pain” as used herein is given its broadest sense and includesan unpleasant sensory and emotional experience associated with actual orpotential tissue damage, or described in terms of such damage andincludes the more or less localized sensation of discomfort, distress,or agony, resulting from the stimulation of specialized nerve endings.There are many types of pain, including, but not limited to, lightningpains, phantom pains, shooting pains, acute pain, inflammatory pain,neuropathic pain, complex regional pain, neuralgia, neuropathy, and thelike (Dorland's Illustrated Medical Dictionary, 28^(th) Edition, W. B.Saunders Company, Philadelphia, Pa.). The present invention isparticularly concerned with the alleviation of inflammatory pain. Thegoal of treatment of pain is to reduce the degree of severity of painperceived by a treatment subject.

By “pharmaceutically acceptable carrier” is meant a solid or liquidfiller, diluent or encapsulating substance that may be safely used intopical, local or systemic administration.

The terms “pharmaceutically compatible salt” and “pharmaceuticallyacceptable salt” are used interchangeably herein to refer to a saltwhich is toxicologically safe for human and animal administration. Thissalt may be selected from a group including hydrochlorides,hydrobromides, hydroiodides, sulfates, bisulfates, nitrates, citrates,tartrates, bitartrates, phosphates, malates, maleates, napsylates,fumarates, succinates, acetates, terephthalates, pamoates andpectinates. Pharmaceutically acceptable salts include both the metallic(inorganic) salts and organic salts; a non-exhaustive list of which isgiven in Remington's Pharmaceutical Sciences 17th Edition, pg. 1418(1985). It is well known to one skilled in the art that an appropriatesalt form is chosen based on physical and chemical stability,flowability, hydroscopicity and solubility.

“Phenylalkyl” means alkyl as defined above which is substituted withphenyl, e.g., —CH₂phenyl, —(CH₂)₂phenyl, —(CH₂)₃phenyl,CH₃CH(CH₃)CH₂phenyl, and the like and derivatives thereof. Phenylalkylis a subset of the aralkyl group.

The terms “polynucleotide variant” and “variant” refer topolynucleotides displaying substantial sequence identity with areference polynucleotide sequence or polynucleotides that hybridize witha reference sequence under stringent conditions as known in the art (seefor example Sambrook et al., Molecular Cloning. A Laboratory Manual”,Cold Spring Harbor Press, 1989). These terms also encompasspolynucleotides in which one or more nucleotides have been added ordeleted, or replaced with different nucleotides. In this regard, it iswell understood in the art that certain alterations inclusive ofmutations, additions, deletions and substitutions can be made to areference polynucleotide whereby the altered polynucleotide retains abiological function or activity of the reference polynucleotide. Theterms “polynucleotide variant” and “variant” also includenaturally-occurring allelic variants.

“Polypeptide”, “peptide” and “protein” are used interchangeably hereinto refer to a polymer of amino acid residues and to variants andsynthetic analogues of the same. Thus, these terms apply to amino acidpolymers in which one or more amino acid residues is a syntheticnon-naturally occurring amino acid, such as a chemical analogue of acorresponding naturally occurring amino acid, as well as to naturallyoccurring amino acid polymers.

The term “polypeptide variant” refers to polypeptides in which one ormore amino acids have been replaced by different amino acids. It is wellunderstood in the art that some amino acids may be changed to otherswith broadly similar properties without changing the nature of theactivity of the polypeptide (conservative substitutions) as describedhereinafter. These terms also encompass polypeptides in which one ormore amino acids have been added or deleted, or replaced with differentamino acids.

The term “prodrug” is used in its broadest sense and encompasses thosecompounds that are converted in vivo to an AT₂ receptor antagonistaccording to the invention. Such compounds would readily occur to thoseof skill in the art, and include, for example, compounds where a freehydroxy group is converted into an ester derivative.

As used herein, “pseudohalides” are groups that behave substantiallysimilar to halides. Such groups can be used in the same manner andtreated in the same manner as halides (X, in which X is a halogen, suchas Cl or Br). Pseudohalides include, but are not limited to cyanide,cyanate, thiocyanate, selenocyanate, trifluoromethyl and azide.

The terms “subject” or “individual” or “patient”, used interchangeablyherein, refer to any subject, particularly a vertebrate subject, andeven more particularly a mammalian subject, for whom therapy orprophylaxis is desired. Suitable vertebrate animals that fall within thescope of the invention include, but are not restricted to, primates,avians, livestock animals (e.g., sheep, cows, horses, donkeys, pigs),laboratory test animals (e.g., rabbits, mice, rats, guinea pigs,hamsters), companion animals (e.g., cats, dogs) and captive wild animals(e.g., foxes, deer, dingoes). A preferred subject is a human in need oftreatment or prophylaxis of inflammatory pain. However, it will beunderstood that the aforementioned terms do not imply that symptoms arepresent.

“Stereoisomers” refer to any two or more isomers that have the samemolecular constitution and differ only in the three dimensionalarrangement of their atomic groupings in space. Stereoisomers may bediastereoisomers or enantiomers. It will be recognized that thecompounds described herein may possess asymmetric centers and aretherefore capable of existing in more than one stereoisomeric form. Theinvention thus also relates to compounds in substantially pure isomericform at one or more asymmetric centers e.g., greater than about 90% ee,such as about 95% or 97% ee or greater than 99% ee, as well as mixtures,including racemic mixtures, thereof. Such isomers may be naturallyoccurring or may be prepared by asymmetric synthesis, for example usingchiral intermediates, or by chiral resolution.

The term “substituted” and variants such as “optionally substituted” asused herein, unless otherwise indicated, mean that a substituent may befurther substituted by one or more additional substituents, which may beoptional or otherwise. Examples of additional substituents includeC₁-C₁₀alkyl, C₃-C₁₀alkenyl, C₃-C₁₀alkynyl, aryl, —(C₁-C₄alkyl)aryl,heterocyclyl, heteroaryl, C₃-C₇-cycloalkyl, C₁-C₄-perfluoroalkyl, —OH,—SH, —HN₂, nitrile, C₁-C₁₀-alkoxy, haloC₁₋₄alkyl, hydroxyC₁₋₄alkyl,C₁-C₁₀-alkylthio, —CF₃, halo (F, Cl, Br, I), —NO₂, —CO₂R²³, —NH₂,C₁-C₄alkylamino, C₁-C₄dialkylamino, arylamino, diarylamino,arylC₁₋₄alkylamino, arylC₁₋₄dialkylamino, aryloxy, arylC₁₋₄alkyloxy,formyl, C₁₋₁₀alkylcarbonyl and C₁₋₁₀alkoxycarbonyl, —PO₃H₂, —CO₂H,—CONHSO₂R²¹, —CONHSO₂NHR²⁰, —NHCONHSO₂R²¹, —NHSO₂R²¹, —NHSO₂NHCOR²¹,—SO₂NHR²⁰, —SO₂NHCOR²¹, —SO₂NHCONHR²⁰, —SO₂NHCO₂R²¹, tetrazolyl, —CHO,—CONH₂, —NHCHO, —CO—(C₁-C₆perfluoroalkyl), —S(O)_(r)—(C₁-C₆perfluoroalkyl), wherein R²⁰ is H, C₁-C₅-alkyl, aryl,—(C₁-C₄-alkyl)-aryl, heteroaryl; R²¹ is aryl, C₃-C₇-cycloalkyl,C₁-C₄-perfluoroalkyl, C₁-C₄alkyl, optionally substituted with asubstituent selected from the group consisting of aryl, heteroaryl, —OH,—SH, C₁-C₄-alkyl, C₁-C₄alkoxy, C₁-C₄alkylthio, —CF₃, halo, —NO₂,—CO₂R²³, —NH₂, C₁-C₄-alkylamino, C₁-C₄-dialkylamino, —PO₃H₂, orheteroaryl; and R²² is selected from C₁-C₆-alkyl, C₃-C₆-cycloalkyl,aryl, —(C₁-C₅-alkyl)-aryl, or heteroaryl.

By “vector” is meant a polynucleotide molecule, preferably a DNAmolecule derived, for example, from a plasmid, bacteriophage, yeast orvirus, into which a polynucleotide can be inserted or cloned. A vectorpreferably contains one or more unique restriction sites and can becapable of autonomous replication in a defined host cell including atarget cell or tissue or a progenitor cell or tissue thereof, or beintegrable with the genome of the defined host such that the clonedsequence is reproducible. Accordingly, the vector can be an autonomouslyreplicating vector, i.e., a vector that exists as an extrachromosomalentity, the replication of which is independent of chromosomalreplication, e.g., a linear or closed circular plasmid, anextrachromosomal element, a minichromosome, or an artificial chromosome.The vector can contain any means for assuring self-replication.Alternatively, the vector can be one which, when introduced into thehost cell, is integrated into the genome and replicated together withthe chromosome(s) into which it has been integrated. A vector system cancomprise a single vector or plasmid, two or more vectors or plasmids,which together contain the total DNA to be introduced into the genome ofthe host cell, or a transposon. The choice of the vector will typicallydepend on the compatibility of the vector with the host cell into whichthe vector is to be introduced. In the present case, the vector ispreferably a viral or viral-derived vector, which is operably functionalin animal and preferably mammalian cells. Such vector may be derivedfrom a poxvirus, an adenovirus or yeast. The vector can also include aselection marker such as an antibiotic resistance gene that can be usedfor selection of suitable transformants. Examples of such resistancegenes are known to those of skill in the art and include the nptII genethat confers resistance to the antibiotics kanamycin and G418(Geneticin®) and the hph gene which confers resistance to the antibiotichygromycin B.

2. Abbreviations

The following abbreviations are used throughout the application:

d=day

h=hour

s=seconds

i.v.=intravenous

i.p.=intraperitoneal

s.c.=subcutaneous

3. Compositions and Methods for the Treatment or Prophylaxis ofInflammatory Pain

The present invention arises from the unexpected discovery that AT₂receptor antagonists are effective in the prevention or attenuation ofthe symptoms of inflammatory pain. These discoveries are based onpre-clinical data which show that administration of AT₂ receptorantagonists to rats with unilateral inflammation of the hindpaw causesalleviation of inflammatory pain. Accordingly, the present inventionprovides methods for treating or preventing inflammatory pain, whereinthe methods generally comprise administering to an individual having, orat risk of developing, inflammatory pain, an effective amount of an AT₂receptor antagonist, which is suitably in the form of a pharmaceuticalcomposition. In accordance with the present invention, the AT₂ receptorantagonist can act to prevent or attenuate one or more symptomsassociated with inflammatory pain including, but not limited to,swelling, redness, hyperalgesia (e.g., mechanical and thermalhyperalgesia), and allodynia. The inflammatory pain may be acute and/orchronic.

There are many possible causes of inflammatory pain and it will beunderstood that the present invention contemplates the treatment orprevention of any inflammatory pain regardless of the cause. Forexample, in some embodiments, the inflammatory pain results from aninfection including but not limited to viral, bacterial or fungalinfections. In other embodiments, the inflammatory pain results from atissue burn, including a burn of the cutaneous tissue (e.g., caused by athermal, chemical, or radiation stimulus) or a sunburn. In still otherembodiments, the inflammatory pain results from an autoimmune diseaseincluding but not restricted to rheumatoid arthritis, inflammatoryarthritis, psoriasis, ankylosing spondylitis, osteoarthritis, colitisand irritable bowel disease. In still other embodiments, theinflammatory pain results from an inflammatory condition of the skin,muscle, or joints (e.g., myocardial infarction, angina, ischemic orthrombotic cardiovascular disease, peripheral vascular occlusivedisease, or peripheral arterial occlusive disease, carditis, dermatitis,myositis, neuritis and collagen vascular diseases). In still otherembodiments, the inflammatory pain results from a cancer. In furtherembodiments, the inflammatory pain results from a traumatic injury orsurgery.

The AT₂ receptor antagonist includes and encompasses any active compoundthat binds to the AT₂ receptor subtype and that suitably inhibits theeffect of angiotensin II signaling through this receptor, includingpharmaceutical compatible salts of the active compound. This categoryincludes compounds having differing structural features. For example, insome embodiments, the AT₂ receptor antagonist is selected from thecompounds listed in U.S. Pat. No. 5,789,415 and especially in thecompound claims of this patent. In illustrative examples of this type,the AT₂ receptor antagonist is selected from compounds having theformula (Ia):

or their pharmaceutically compatible salts,

wherein:

Q is naphthyl, a 5 to 7 member heterocycle having from 1 to 3 atomsindependently selected from nitrogen, oxygen and sulfur, or an 8 to 11member heterobicycle having from 1 to 4 atoms selected from nitrogen,oxygen and sulfur, said heterocycle or heterobicycle being saturated,partially saturated or unsaturated and said naphthyl, heterocycle orheterobicycle optionally substituted with 1 to 4 W¹ substituents;

each W¹ substituent is independently selected from halo, hydroxy, nitro,cyano, C₁ to C₈ alkyl, C₃ to C₇ cycloalkyl, C₁ to C₇ alkoxy, amino, C₁to C₇ alkylamino, di(C₁ to C₇ alkyl)amino, C₁ to C₇ alkylthio, C₁ to C₇alkylsulfinyl, C₁ to C₇ alkylsulfonyl, —CONRR, —COOR and phenyl, saidalkyl, cycloalkyl, alkoxy, alkylamino, dialkylamino, alkylthio,alkylsulfinyl and alkylsulfonyl optionally substituted with 1 or more W²substituents, and said phenyl optionally substituted with 1 or more W³substituents;

each R is independently hydrogen or C₁ to C₈ alkyl, said alkyloptionally substituted with 1 or more W² substituents;

each W² substituent is independently selected from halo, hydroxy, oxo,C₃ to C₇ cycloalkyl, C₁ to C₇ alkoxy, acyloxy, phenyl and 5 to 7 memberheterocycle having 1 to 3 atoms selected from nitrogen, oxygen andsulfur, said phenyl and heterocycle optionally substituted with 1 ormore W³ substituents;

each W³ substituent is independently selected from halo, hydroxy, nitro,C₃ to C₇ cycloalkyl, C₁ to C₇ alkoxy, amino, C₁ to C₇ alkylamino, di(C₁to C₇ alkyl)amino, C₁ to C₇ alkylthio, C₁ to C₇ alkylsulfinyl and C₁ toC₇ alkylsulfonyl;

R¹ and R², when taken separately, are each independently selected fromhydrogen, hydroxy, C₁ to C₁₀ alkyl, C₁ to C₇ alkylthio, C₁ to C₇alkylsulfinyl, C₁ to C₇ alkylsulfonyl, phenyl and 5 to 7 memberheterocycle or 8 to 11 member heterobicycle, having 1 to 3 atomsselected from nitrogen, oxygen and sulfur, said alkyl, alkylthio,alkylsulfinyl and alkylsulfonyl optionally substituted with 1 or more W⁴substituents, said phenyl and said heterocycle and heterobicycleoptionally substituted with 1 to 5 W³ substituents, wherein the W³substituents are as defined above, and said heterocycle being saturated,partially saturated or unsaturated, provided that R¹ and R² are not bothhydroxy;

R¹ and R², when taken together with the carbon atom to which they areattached, form a C₃ to C₇ carbocyclic, C₇ to C₁₁ carbobicyclic, 3 to 7member heterocyclic group having from 1 to 3 atoms independentlyselected from nitrogen, oxygen and sulfur, or a 7 to 11 memberheterobicyclic group having from 1 to 4 atoms independently selectedfrom nitrogen, oxygen and sulfur, said carbocyclic, carbobicyclic,heterocyclic or heterobicyclic group being saturated, partiallysaturated or unsaturated and optionally substituted with 1 or more W⁵substituents;

each W⁴ substituent is independently selected from halo, C₃ to C₈cycloalkyl, phenyl and 5 to 7 member heterocycle having 1 to 3 atomsselected from nitrogen, oxygen and sulfur, said phenyl and heterocycleoptionally substituted with 1 or more substituents independentlyselected from halo, hydroxy, nitro, C₁ to C₁₀ alkyl, C₃ to C₇cycloalkyl, C₁ to C₇ alkoxy, amino, C₁ to C₇ alkylamino and di(C₁ to C₇alkyl)amino;

each W⁵ substituent is independently selected from halo, hydroxy, nitro,cyano, oxo, C₁ to C₈ alkyl, C₃ to C₇ cycloalkyl, C₁ to C₇ alkoxy, amino,C₁ to C₇ alkylamino, di(C₁ to C₇ alkyl)amino, C₁ to C₇ alkylthio, C₁ toC₇ alkylsulfinyl, C₁ to C₇ alkylsulfonyl, —CONRR, —COOR and phenyl, saidalkyl, cycloalkyl, alkoxy, alkylamino, dialkylamino, alkylthio,alkylsulfinyl and alkylsulfonyl groups optionally substituted with 1 ormore W² substituents, and said phenyl optionally substituted with 1 ormore W³ substituents, wherein the W³ substituents are as defined above;

R³ is —(CH₂)_(n) COR⁴, tetrazolyl, C₁ to C₅ alkyltetrazolyl, triazolyl,C₁ to C₅ alkyltriazolyl, —(CH2)_(n)CH₂OH, —SO₂R⁴, —SO₂NR⁵R⁶ or —NHSO₂R⁷;

R⁴ is hydrogen, hydroxy, —NHSO₂R⁷, C₁ to C₁₀ alkoxy, C₁ to C₇ alkylthio,—NR⁵R⁶, —NHSO₂R⁷ or —OY, said alkoxy and alkylthio groups optionallysubstituted with 1 or more W⁶ substituents;

n is an integer from 0 to 5;

Y is a pharmaceutically acceptable cation or a group hydrolyzable underphysiological conditions;

R⁵ and R⁶, when taken separately, are each independently hydrogen,hydroxy, cyano, C₁ to C₁₀ alkyl, C₁ to C₈ alkoxy, —COR, —CONRR, —COOR,phenoxy, —CO(C₆H₅) or 5 to 6 member heterocycle having 1 to 4 atomsselected from nitrogen, oxygen and sulfur, wherein R is as definedabove, said alkyl optionally substituted with 1 or more W³ substituents,wherein the W³ substituents are as defined above, said —CO(C₆H₅)optionally substituted with 1 to 3 W⁶ substituents and said heterocycleoptionally substituted with 1 or more W⁵ substituents, wherein the W⁵substituents are as defined above;

R⁵ and R⁶, when taken together with the nitrogen atom to which they areattached, form a 3 to 7 member ring having 1 to 3 nitrogen atoms andfrom 0 to 3 atoms selected from oxygen and sulfur, said ring beingsaturated, partially saturated or unsaturated and optionally substitutedwith 1 or more W¹ substituents, wherein the W¹ substituents are asdefined above;

R⁷ is C₁ to C₁₀ alkyl or phenyl, said alkyl optionally substituted with1 or more W⁶ substituents, and said phenyl optionally substituted with 1or more W³ substituents, wherein the W³ substituents are as definedabove;

X is an azacyclic group of the formula:

L¹, L², L³, L⁴ and L⁵, when taken separately, are independentlyhydrogen, halo, nitro, C₁ to C₆ alkyl, C₃ to C₇ cycloalkyl,polyfluoro-C₁ to C₄ alkyl, aryl, heteroaryl, tetrazol-5-yl, —COR⁸,—CO₂R⁸, —CONHSO₂R⁹, —CONR¹⁶R¹⁶, —CONH (tetrazol-5-yl), —OR⁹, —OCONR⁹R¹¹,—NR⁸R⁹, —NHCOR⁹, —NHCO₂R⁹, —NHCONR⁸R⁹, —NHSO₂R⁹, —NHSO₂NR⁹R¹¹,—NHSO₂-polyfluorophenyl, —SR⁹, —SOR⁹, —SO₂R⁹, —SO²NHCN, —SO₂NR¹¹R¹²,—SO₂NHCOR⁹, —SO₂NH-heteroaryl, —PO(OR⁸)₂ or —PO(OR⁸)R¹¹, said alkyl,cycloalkyl, aryl and heteroaryl groups optionally substituted with 1 ormore substituents selected from hydroxy, halo, C₁ to C₄ perfluoroalkyl,C₁ to C₄ alkoxy, aryl, heteroaryl, guanidino, morpholino, tetrazol-5-yl,—COR⁸, —CO₂R⁸, —CONHSO₂R⁹, —CONR⁸R⁸, —O—COR⁸, —NR⁸R⁸, —NR¹²COOR⁹, —N(C₁to C₆ alkyl)piperazine, —SR⁹, —SOR⁹, —SO₂R⁹, —SO₂NR⁸CN, —SO₂NR⁸COR⁹,—SO₂NR⁸-heteroaryl, —PO(OR⁸)₂ and —PO(OR⁸)R¹³;

L¹ and L², L² and L³, L³ and L⁴ or L⁴ and L⁵, when taken together withthe azacyclic group to which they are attached, form a fused 8 to 11member azabicyclic system having 1 to 5 nitrogen atoms and 0 to 3 atomsselected from oxygen and sulfur, said azabicyclic system optionallysubstituted with 1 to 3 W⁶ substituents;

each W⁶ substituent is independently halo, nitro, cyano, C₁ to C₆ alkyl,C₃ to C₇ cycloalkyl, polyfluoro-C₁ to C₄ alkyl, aryl, heteroaryl,tetrazol-5-yl, —COR⁸, —CO₂R⁸, —CONR⁸SO₂R⁹, —CONR⁹R¹⁰,—CONR⁸(tetrazol-5yl), —OR⁹, —OCONR⁹R¹¹, —NR⁸R⁹, —NR⁸COR⁹, —NR⁸CO₂R⁹,—NR⁸CONR⁸R⁹, —NR⁸SO₂R⁹, —NR⁸SO₂NR₉R¹¹, —NR⁸SO₂-polyfluorophenyl, —SR⁹,—SOR⁹, —SO₂R⁹, —SO₂NR₈CN, —SO₂NR⁹R¹², —SONR⁸COR⁹, —SO₂NR⁸-heteroaryl,—PO(OR⁸)₂ or —PO(OR⁸)R¹¹, said alkyl, cycloalkyl, aryl and heteroarylgroups optionally substituted with 1 or more substituents selected fromhydroxy, halo, C₁ to C₄ perfluoroalkyl, C₁ to C₄ alkoxy, aryl,heteroaryl, guanidino, morpholino, tetrazol-5-yl, —COR⁸, —CO₂R⁸,—CONR⁸SO₂R⁹, —CONR⁸R⁹, —O—COR⁸, —NR⁸R⁹, —NR¹²COOR⁹, —N(C₁ to C₆alkyl)piperazine, —SR⁹, —SOR⁹, —SO₂R⁹, —SO₂NR⁸CN, —SO₂NR⁸COR⁹,—SO₂NR⁸-heteroaryl, —PO(OR⁸)₂ and —PO(OR⁸)R¹³;

each R⁸ is independently hydrogen, C₁ to C₆ alkyl, C₃ to C₇ cycloalkyl,aryl, heteroaryl or aryl(C₁ to C₆)alkyl;

each R⁹ is independently hydrogen, C₁ to C₁₀ alkyl, C₃ to C₇ cycloalkyl,aryl, heteroaryl or polyfluoro(C₁ to C₄)alkyl, said alkyl and cycloalkyloptionally substituted with 1 or more substituents selected from halo,hydroxy, nitro, C₁ to C₄ alkoxy, C₁ to C₄ alkylthio, —CO₂R¹², amino, C₁to C₄ alkylamino, di(C₁ to C₄)alkylamino, aryl, heteroaryl, —SH, —PO₃H₂,—P(O)(OH)(O—C₁ to C₄ alkyl), P(O)(OR⁸)(R¹¹) or P(O)(OR¹⁴)(R¹⁵);

each R¹⁰ is independently hydrogen, C₁ to C₅ alkyl, aryl or —CH₂-aryl;

each R₁₁ is independently hydrogen, C₁ to C₅ alkyl, C₃ to C₇ cycloalkyl,aryl or —CH₂-aryl;

each R¹² is hydrogen or C₁ to C₄ alkyl;

each R¹³ is independently hydrogen, C₁ to C₅ alkyl, C₂ to C₄ alkenyl, C₁to C₄ alkoxy(C₁ to C₄)alkyl or benzyl, said benzyl optionallysubstituted with 1 or more substituents independently selected fromhydroxy, amino, nitro and methoxy;

R¹⁴ and R¹⁵ are taken together and form a 5 to 7 member ring having 1 to3 atoms independently selected from nitrogen, oxygen and sulfur;

M¹ and M² are taken together and are —(CH₂)_(m); and

m is an integer from 3 to 7.

Preferred compounds are those of formula (I) wherein:

X is

L¹, L² and L⁴ are as defined above;

Q is thiophene, pyridine, pyrimidine, naphthyl, benzofuran or any of theforegoing substituted with 1 or 2 W¹ substituents; R¹ and R² are takentogether as defined above;

R³ is —(CH₂)_(n) COR⁴; n is 0 or 1; R⁴ is hydrogen, hydroxy or —OY;

Y is a pharmaceutically acceptable cation or a group hydrolyzable underphysiological conditions; and

each W¹ is independently halo, hydroxy, C₁ to C₈ alkyl, C₃ to C₇cycloalkyl, C₁ to C₇ alkoxy, amino, C₁ to C₇ alkylamino, di(C₁ to C₇alkyl)amino, —CONRR or —COOR, wherein R is as defined above.

Particularly preferred are those compounds wherein X, Q, R³, R⁴, n and Yare as defined immediately above and wherein:

R¹ and R² are taken together and form a C₅ to C₆ carbocyclic, C₈ to C₁₀carbobicyclic or 5 to 7 member heterocyclic group having 1 or 2 atomsindependently selected from nitrogen, oxygen and sulfur, saidcarbocyclic, carbobicyclic or heterocyclic group being saturated,partially saturated or unsaturated;

L¹ and R², when taken separately, are each independently hydrogen, halo,C₁ to C₆ alkyl, C₃ to C₇ cycloalkyl, polyfluoro-C₁ to C₄ alkyl or—CO₂R⁸;

L¹ and L², when taken together with the azacyclic group to which theyare attached, form a fused 8 to 10 member azabicyclic system having 2 to4 nitrogen atoms, said azabicyclic system optionally substituted with 1to 3 W⁶ substituents;

L⁴ is C₁ to C₄ alkyl, C₃ to C₅ cycloalkyl or C₁ to C₃ alkoxy;

R⁸ is hydrogen, C₁ to C₆ alkyl or C₃ to C₇ cycloalkyl; and

each W⁶ is independently halo, C₁ to C₆ alkyl, C₃ to C₇ cycloalkyl,polyfluoro-C₁ to C₄ alkyl, —CO₂R⁸, amino, C₁ to C₆ alkylamino, di(C₁ toC₆)alkylamino, acylamino or diacylamino.

Among the particularly preferred compounds defined above are thosehaving the structure:

wherein:

L4 is C₁ to C₄ alkyl or C₃ to C₅ cycloalkyl;

each W⁶ is independently C₁ to C₆ alkyl, amino, C₁ to C₆ alkylamino,di(C₁ to C₆)alkylamino, acylamino or diacylamino; and

R¹ and R² are taken together and form cyclopentane, cyclohexane,cyclopentene, tetrahydropyran or indan, for example:

-   1-[5-(2-ethyl-5,7-dimethylimidazo[4.5-b]pyridin-3-ylmethyl)thiophen-2-yl]-cyclopent-3-ene    carboxylic acid;-   1-[5-(5,7-dimethyl-2-propylimidazo[4.5-b]pyridin-3-ylmethyl)thiophen-2-yl]cyclopent-3-ene    carboxylic acid;-   1-[5-(2-cyclopropyl-5,7-dimethylimidazo[4.5-b]pyridin-3-ylmethyl)thiophen-2yl]cyclopent-3-ene    carboxylic acid;-   1-[5-(2-cyclopropyl-5,7-dimethylimidazo[4.5-b]pyridin-3-ylmethyl)thiophen-2yl]cyclopentane    carboxylic acid;-   4-[5-(2-ethyl-5,7-dimethylimidazo[4.5-b]pyridin-3-ylmethyl)thiophen-2-yl]tetrahydropyran-4-carboxylic    acid;-   2-[5-(2-ethyl-5,7-dimethylimidazo[4.5-b]pyridin-3-ylmethyl)thiophen-2-yl]indan-2-carboxylic    acid;-   2-[5-(2-cyclopropyl-5,7-dimethylimidazo[4,5-b]pyridin-3-ylmethyl)thiophen-2yl]indan-2-carboxylic    acid;-   1-[5-(2-ethyl-5,7-dimethylimidazo[4,5-b]pyridin-3-ylmethyl)thiophen-2-yl]cyclohexane    carboxylic acid; and-   1-[5-(2-cyclopropyl-5,7-dimethylimidazo[4.5-b]pyridin-3-ylmethyl)thiophen-2-yl]cyclohexane    carboxylic acid.

Also among the particularly preferred compounds defined above are thosehaving the structure

wherein:

Q is

L⁴ is C₁ to C₄ alkyl or C₃ to C₅ cycloalkyl; and

R¹ and R² are taken together and are —CH₂CH₂CH₂CH₂— or —CH₂CH═CHCH₂—,for example:

-   1-[5-(2-ethyl-5,7-dimethylimidaz[4.5-b]pyridin-3-ylmethyl)pyridin-2-yl]cyclopentane    carboxylic acid;-   1-[5-(2-cyclopropyl-5,7-dimethylimidazo[4.5-b]pyridin-3-ylmethyl)pyridin-2-yl]cyclopentane    carboxylic acid;-   1-[2-(2-ethyl-5,7-dimethylimidazo[4.5-b]pyridin-3-ylmethyl)pyrimidin-5-yl]cyclopent-3-ene    carboxylic acid;-   1-[2-(2-cyclopropyl-5,7-dimethylimidazo[4.5-b]pyridin-3-ylmethyl)pyrimidin-5-yl]cyclopent-3-ene    carboxylic acid;-   1-[6-(2-ethyl-5,7-dimethylimidazo[4.5-b]pyridin-3-ylmethyl)naphthalen-2-yl]cyclopent-3-ene    carboxylic acid; and-   1-[3-bromo-5-(2-ethyl-5,7-dimethylimidazo[4.5-b]pyridin-3-ylmethyl)benzofuran-2-yl]cyclopentane    carboxylic acid.

Also among the particularly preferred compounds defined above are thosehaving the structure

wherein:

Q is

L¹ and L² are taken separately and are each independently halo, C₁ to C₆alkyl or —CO₂H;

L⁴ is C₁ to C₄ alkyl; and

R¹ and R² are taken together and are —CH₂CH₂CH₂CH₂— or —CH₂CH═CHCH₂—,for example:

-   2-butyl-3-[5-(1-carboxycyclopent-3-enyl)thiophen-2-ylmethyl]-5-chloro-3H-imidazole-4-carboxylic    acid;-   3-[5-(1-carboxycyclopent-3-enyl)thiophen-2-ylmethyl]-5-ethyl-2-propyl-3H-imidazole-4-carboxylic    acid; and-   3-[5-(1-carboxycyclopent-3-enyl)thiophen-2-ylmethyl]-5-chloro-2-propyl-3H-imidazole-4-carboxylic    acid.

Also among the particularly preferred compounds defined above are thosehaving the structure

wherein:

Q is

L⁴ is C₁ to C₄ alkyl; and

R¹ and R² are taken together and are —CH₂CH₂CH₂CH₂— or —CH₂CH═CHCH₂—,for example:

-   1-[5-(2-butyl-5-methyl-4-oxo-4H-quinazolin-3-ylmethyl)pyridin-2-yl]cyclopentane    carboxylic acid; and-   1-[5-(2-butyl-5-methyl-4-oxo-4H-quinazolin-3-ylmethyl)thiophen-2-yl]cyclopent-3-ene    carboxylic acid.

Also among the particularly preferred compounds defined above are thosehaving the structure

wherein:

L¹ and L² are taken separately and are each independently halo, C₁ to C₆alkyl, polyfluoro-C₁ to C₆ alkyl or —CO₂H;

L⁴ is C₁ to C₄ alkyl; and

R¹ and R₂ are taken together and are —CH₂CH₂CH₂CH₂— or —CH₂CH═CHCH₂—,for example:

-   2,5-dibutyl-4-[5-(1-carboxycyclopent-3-enyl)thiophen-2-ylmethyl]-2H-pyrazole-3-carboxylic    acid;-   5-butyl-4-[5-(1-carboxycyclopent-3-enyl)thiophen-2-ylmethyl]-2-trifluoromethyl-2H-pyrazole-3-carboxylic    acid; and-   5-butyl-4-[5-(1-carboxycyclopent-3-enyl)thiophen-2-ylmethyl]-2-propyl-2H-pyrazole-3-carboxylic    acid.

Other preferred compounds include compounds in the same general classas:

-   1-[5-(2-cyclopropyl-5,7-dimethylimidazo[4.5-b]pyridin-3-ylmethyl)thiophen-2-yl]cyclopenten-3-ene    carboxylic acid benzenesulfonamide;-   1-[5-(2-cyclopropyl-5,7-dimethylimidazo[4.5-b]pyridin-3-ylmethyl)thiophen-2-yl]cyclopenten-3-ene    carboxylic acid p-toluenesulfonamide;-   1-[5-(2-cyclopropyl-5,7-dimethylimidazo[4.5-b]pyridin-3-ylmethyl)thiophen-2-yl]cyclopenten-3-ene    carboxylic acid methanesulfonamide; and-   1-[5-(2-cyclopropyl-5,7-dimethylimidazo[4.5-b]pyridin-3-ylmethyl)thiophen-2-yl]cyclopenten-3-ene    carboxylic acid trifluoromethanesulfonamide.

Various intermediates also fall within the scope of the presentinvention, including:

-   1-thiophen-2-yl-cyclopent-3-ene carboxylic acid ethyl ester;-   1-(5-formylthiophen-2-yl)cyclopent-3-ene carboxylic acid ethyl    ester;-   1-(5-chloromethylthiophen-2-yl)cyclopent-3-ene carboxylic acid ethyl    ester; and-   1-[5-(2-ethyl-5,7-dimethylimidazo>4,5-b!pyridin-3-ylmethyl)thiophen-2-yl!cyclopent-3-ene    carboxylic acid ethyl ester.

In other embodiments, the AT₂ receptor antagonist is selected from4,5,6,7-tetrahydro-1H-imidazo[4,5-c]pyridine-6-carboxylic acid analogsas described for example in U.S. Pat. No. 4,812,462 and especially inthe compound claims of this patent. In illustrative examples of thistype, the AT₂ receptor antagonist is selected from compounds having theformula (Ib):

or their pharmaceutically compatible salts,

wherein:

(1) — is a single or a double bond;

(2) one of R₁ is present and is

-   -   (a) alkyl of from four to twenty carbons, inclusive,    -   (b)

-   -   wherein y is zero, one, two, three, four or five, R′ is        cycloalkyl of from four to twenty carbons, inclusive in a one,        two or three saturated ring system, said ring consisting of from        four to eight carbons inclusive, each ring unsubstituted or        substituted by a straight or branched lower alkyl group,        naphthyl, heteroaryl consisting of 2-, 3-, or 4-pyridyl; 1-, 2-,        or 4-imidazolyl; 1-, 2-, 3-, 4-, 5-, 6-, or 7-indolyl; 2-, or        3-thienyl; 2-, or 3-furyl; or 1-, 2-, or 3-pyrazolyl, phenyl        unsubstituted or substituted with of from one through five        substituents selected from the group consisting of lower alkyl,        halo, trifluoromethyl, hydroxy, lower alkoxy, lower alkyl        acyloxy, amino, N-lower monoalkylamino, N,N-lower dialkylamino,        lower thioalkyl, lower alkylsulfonyl, nitro and

-   -   wherein R₁₀ is lower alkyl, phenyl unsubstituted or substituted        by lower alkyl, or —NHR₁₁ wherein R₁₁ is hydrogen or lower        alkyl, and R″ is hydrogen, lower alkyl, cycloalkyl of from four        to twenty carbons, inclusive in a one two or three saturated        ring system, said ring consisting of from four to eight carbons        inclusive, each ring unsubstituted or substituted by a straight        or branched lower alkyl group, naphthyl, phenyl unsubstituted or        substituted with of from one through five substituents selected        from the group consisting of alkyl, halo, trifluoromethyl,        amino, N-lower monoalkylamino, N,N-lower dialkylamino, lower        thioalkyl, lower alkylsulfonyl, and nitro;

(3) R₂ is

-   -   (a) hydrogen,    -   (b) halo,    -   (c) lower alkyl,    -   (d) R′—(CH₂)—_(x) wherein x is one, two, three, four, or five        and R′ is independently as defined above,    -   (e)

-   -   wherein R′ is independently as defined above, or    -   (f) R′—CH(OH)— wherein R′ is independently as defined above;

(4) R₃ is

-   -   (a) R′—CH₂)_(x) wherein x and R′ are independently as defined        above,    -   (b)

-   -   wherein R′ and y are independently as defined above, and R′″ is        lower alkyl, cycloalkyl, of from four to twenty carbons,        inclusive in a one, two or three saturated ring system, said        ring consisting of from four to eight carbons inclusive, each        ring unsubstituted or substituted by a straight or branched        lower alkyl group, naphthyl, phenyl unsubstituted or substituted        with of from one to five substituents selected from the group        consisting of alkyl, halo, trifluoromethyl, amino, N-lower        monoalkylamino, N,N-lower dialkylamino, lower thioalkyl, lower        alkylsulfonyl, and nitro;    -   (c)

-   -   wherein R₅ is        -   (i) alkyl of from one to fifteen carbons, inclusive,        -   (ii)

-   -   -   wherein R′, R″, and y are independently as defined above,

CH═CR₆R₁  (iii)

-   -   -   wherein R₆ is hydrogen or lower alkyl and R₁ is as defined            above,        -   (iv)

-   -   -   wherein y, R′ and R₆ are independently as defined above,

R′CH₂_(y)—O—  (v)

-   -   wherein y and R′ are independently as defined above,    -   (vi)

-   -   wherein R′, R″, and y are independently as defined above,    -   (d)

-   -   wherein R₅ is independently as defined above;

(5) R₄ is

-   -   (a) —CH₂OR₇ wherein R₇ is hydrogen, lower acyl, a lower alkyl,    -   (b)

-   -   wherein R₇ is independently as defined above and R₈ is hydrogen,        lower alkyl, or benzyl,    -   (c)

-   -   (d) —C≡N,    -   (e)

-   -   wherein R₉ is hydrogen, lower alkyl, or benzyl; and    -   (6) n is one; with the overall proviso that R₉ cannot be        hydrogen, methyl or ethyl when R₃ is R′—(CH₂)—_(x) or

-   -   wherein R₅ is R′(CH₂)_(y)O— or

-   -   wherein each of R′, R″, x, and y are as defined above.

In some embodiments, the compounds according to formula (Ib) have astructure wherein R₂ is H, n is one and R₃ is

wherein R₅ is as defined above, R₄ is as defined above and R₁ is asdefined above.

In some embodiments, the compounds according to formula (Ib) have astructure wherein R₃ is

wherein R₅ is as defined above.

In specific embodiments, the compounds according to formula (Ib) areselected from:

-   1-(4-Dimethylamino-3-methylphenyl)methyl-5-diphenylacetyl-4,5,6,7-tetrahydro-1H-imidazo[4,5-c]-pyridine-6-carboxylic    acid (PD-123,319);-   1-(3-methyl-4-methoxyphenyl)-methyl-5-diphenylacetyl-4,5,6,7-tetrahydro-1H-imidazo(4,5-c)pyridine-6-carboxylic    acid (PD-121,981); and-   1-((4-amino-3-methylphenyl)methyl)-5-(diphenylacetyl)-4,5,6,7-tetrahydro-1H-imidazo(4,5c)pyridine-6-carboxylic    acid (PD-123,177), or their prodrugs or pharmaceutically acceptable    salts.

In other embodiments, the AT₂ receptor antagonist is selected fromsubstituted 1,2,3,4-tetahydroisoquinolines as described for example inU.S. Pat. No. 5,246,943 and especially in the compound claims of thispatent. In illustrative examples of this type, the AT₂ receptorantagonist is selected from compounds having the formula (Ic):

or their pharmaceutically compatible salts,

wherein:

R₁ and R₂ are each independently hydrogen, lower alkyl, halogen,hydroxy, alkoxy, amino, alkylamino, dialkylamino, acylamino, CF₃,carboxy, carboalkoxy, hydroxyalkyl, aminoalkyl, and nitro;

n is an integer from zero to 4;

X is absent, O, S, NH, N-alkyl, and is attached to thetetrahydroisoquinoline at the 5 or 6 position;

R₃ is hydrogen, alkoxy, aryloxy, alkylthio, or halogen attached eitherat the 6, 7, or 8 position;

R₄ is hydrogen, alkyl, hydroxyalkyl, CO₂R₆, CON(R₆)₂ wherein R₆ ishydrogen or lower alkyl; and

R₅ is alkyl, aryl, aralkyl which can be unsubstituted or substituted onthe alkyl and/or on the aryl portion, diaralkyl (the aryl portion can beunsubstituted or substituted), COR₇, SO₂R₇ wherein R₇ is aralkyl, alkyl,diaralkyl, OR₈, NR₈R₉ wherein R₈ and R₉ are each independently hydrogen,alkyl, cycloalkyl, aryl, or aralkyl.

In some embodiments, the compounds according to formula (Ic) are thosewherein:

R₁ and R₂ are each independently hydrogen, lower alkyl, alkoxy, amino,carboxy, and nitro;

n is an integer of from 0 to 3;

X is O, S, or NH substituted at the 5 position;

R₃ is hydrogen, alkoxy, or halogen substituted at the 6 position;

R₄ is hydrogen, alkyl, hydroxyalkyl, CO₂R₆, CON(R₆)₂; and

R₅ is alkyl, aryl, or COR₇.

In some embodiments, the compounds according to formula (Ic) are thosewherein:

R₁ and R₂ are each independently hydrogen, lower alkyl, alkoxy, carboxy,and nitro;

n is an integer of from 0 to 2;

X is O substituted at the 5 position;

R₃ is alkoxy substituted at the 6 position;

R₄ is CO₂R₆, or CON(R₆)₂; and

R₅ is COR₇ wherein R₇ is diaralkyl or NR₈R₉ wherein R₈ and R₉ are eachindependently hydrogen, alkyl, or aryl and the aryl group may besubstituted.

In specific embodiments, the compounds according to formula (Ic) arethose wherein:

R₁ and R₂ are each independently hydrogen, methoxy, carboxy, methyl,nitro, or amino;

n is 0, 1, or 2;

X is O, NH;

R₃ is H, or —OCH₃;

R₄ is —COOH, COOCH₃, COOC₂H₅, CONH₂, and

and

R₅ is hydrogen,

In certain embodiments, the compounds according to formula (Ic) possessone or more chiral centres and each centre may exist in the R or Sconfiguration.

Representative examples of compounds according to formula (Ic) include,but are not limited to:

-   2-(Diphenylacetyl)-6-ethoxy-1,2,3,4-tetrahydro-5-(phenylmethoxy)-3-isoquinoline    carboxylic acid;-   2-(Diphenylacetyl)-1,2,3,4-tetrahydro-6    methoxy-5-(phenylmethoxy)-3-isoquinoline carboxylic acid;-   2-(2,2-Diphenylethyl)-1,2,3,4    tetrahydro-6-methoxy-5-(phenylmethoxy)-3-isoquinolinecarboxylic    acid;-   2-Butyl-1,2,3,4-tetrahydro-6-methoxy    5-(phenylmethoxy)-3-isoquinoline carboxylic acid;-   2-(Diphenylacetyl)-1,2,3,4-tetrahydro-6-methoxy-5-(phenylmethoxy)-3-isoquinoline    carboxylic acid;-   2-[(Diphenylmethyl)sulfonyl]-1,2,3,4    tetrahydro-6-methoxy-5-(phenylmethoxy)-3 isoquinoline carboxylic    acid;-   1,2,3,4-Tetrahydro-6-methoxy-2-phenyl    5-(phenylmethoxy)-3-isoquinolinecarboxylic acid;-   5-[(4 Aminophenyl)methoxy]-2-(diphenylacetyl)    1,2,3,4-tetrahydro-6-methoxy-3 isoquinoline carboxylic acid;-   5-[(4 Amino-3-methylphenyl)methoxy]-2-(diphenyl    acetyl)-1,2,3,4-tetrahydro-6-methoxy-3-isoquinoline carboxylic acid;-   5-[[4-(Dimethylamino)-3    methylphenyl]methoxy]-2-(diphenylacetyl)-1,2,3,4-tetrahydro-6-methoxy-3-isoquinoline    carboxylic acid;-   (S)-2-(Diphenylacetyl)-1,2,3,4-tetrahydro-6-methoxy-5-(phenylmethoxy)-3-isoquinoline    carboxylic acid;-   (R)-2    (Diphenylacetyl)-1,2,3,4-tetrahydro-6-methoxy-5-(phenylmethoxy)-3-isoquinoline    carboxylic acid;-   2-(Diphenylacetyl)-1,2,3,4-tetrahydro-6-methoxy    5-[(phenylmethyl)thio]-3-isoquinolinecarboxylic acid;-   2-(Diphenylacetyl)-1,2,3,4    tetrahydro-6-(methylthio)-5-(phenylmethoxy)-3-isoquinolinecarboxylic    acid;-   2-(Diphenylacetyl)-1,2,3,4-tetrahydro-6-methoxy-5-[(phenylmethyl)amino]-3-isoquinoline    carboxylic acid;-   2-(Diphenylacetyl)-1,2,3,4-tetrahydro-6-methoxy-5-[methyl(phenylmethyl)amino]-3-isoquinoline    carboxylic acid;-   2-(Diphenylacetyl)-1,2,3,4 tetrahydro    6-methoxy-5-(phenylthio)-3-isoquinolinecarboxylic acid;-   2-(Diphenylacetyl)-1,2,3,4-tetrahydro-6-methoxy-5-(phenylthio)-3-isoquinoline    carboxylic acid;-   2-(Diphenylacetyl)-1,2,3,4-tetrahydro-6-methoxy-5-[methyl(phenylamino)]-3-isoquinoline    carboxylic acid;-   2-(Diphenylacetyl)-1,2,3,4    tetrahydro-6-methoxy-5-(phenylmethyl)-3-isoquinoline carboxylic    acid;-   2-(Diphenylacetyl)-1,2,3,4-tetrahydro-6-methoxy-5-(2-phenylethyl)-3-isoquinoline    carboxylic acid;-   2-(Diphenylacetyl)-1,2,3,4    tetrahydro-6-methoxy-5-phenyl-3-isoquinoline carboxylic acid;-   2-(Diphenylacetyl)-1,2,3,4-tetrahydro-5-(phenylmethoxy)-3-isoquinolinecarboxylic    acid;-   2-(Diphenylacetyl)-1,2,3,4-tetrahydro-6-methoxy-5-(phenylmethoxy)-3-isoquinoline    carboxamide;-   2-(Diphenylacetyl)-1,2,3,4-tetrahydro    N,N-dimethyl-6-methoxy-5-(phenylmethoxy)-3-isoquinoline carboxamide;-   2-(Diphenylacetyl)-1,2,3,4-tetrahydro-6-methoxy-5-(phenylmethoxy)-3-isoquinoline    carboxylic acid;-   2-(Diphenylacetyl)-1,2,3,4-tetrahydro-7-methoxy-6-(phenylmethoxy)-3-isoquinoline    carboxylic acid;-   2-(Diphenylacetyl)-1,2,3,4-tetrahydro-6-methoxy-5-(2-phenylethoxy)-3-isoquinoline    carboxylic acid;-   2-[Bis(4-chlorophenyl)acetyl]-1,2,3,4-tetrahydro-6-methoxy-5-(phenylmethoxy)-3-isoquinoline    carboxylic acid;-   2-(Cyclopentylphenylacetyl)-1,2,3,4-tetrahydro-6-methoxy-5-(phenylmethoxy)-3-isoquinoline    carboxylic acid;-   2-[(2,6-Dichlorophenyl)acetyl]-1,2,3,4-tetrahydro-6-methoxy-5-(phenylmethoxy)-3-isoquinoline    carboxyli acid;-   1,2,3,4-Tetrahydro-6 methoxy-2-[(methylphenyl    amino)carbonyl]-5-(phenylmethoxy)-3-isoquinoline carboxylic acid;-   1,2,3,4-Tetrahydro-6-methoxy-2-[[(4-methoxy    phenyl)amino]carbonyl]-5-(phenylmethoxy)-3-isoquinoline carboxylic    acid;-   2-[[(4-Fluorophenyl)amino]carbonyl]-1,2,3,4-tetrahydro-6-methoxy-5-(phenylmethoxy)-3-isoquinolinecarboxylic    acid;-   2-(Diphenylacetyl)-1,2,3,4-tetrahydro-6-methoxy-5-phenylmethoxy-3-isoquinoline    carboxylic acid, ethyl ester;-   5-[(4-Carbomethoxyphenyl)methoxy]-2-(diphenyl    acetyl)-1,2,3,4-tetrahydro 6-methoxy-3-isoquinoline carboxylic acid,    ethyl ester;-   5-(4-Carboxyphenylmethoxy)-2-(diphenylacetyl)    1,2,3,4-tetrahydro-6-methoxy-3-isoquinolinecarboxylic acid;-   2-(Diphenylacetyl)-1,2,3,4-tetrahydro-6-methoxy-5-[(4-methoxy-3-methylphenyl)methoxy]-3-isoquinoline    carboxylic acid, ethyl ester;-   2-(Diphenylacetyl)-1,2,3,4-tetrahydro-6-methoxy-5-[(4-methoxy-3-methylphenyl)methoxy]-3-isoquinoline    carboxylic acid;-   2-(Diphenylacetyl)-1,2,3,4-tetrahydro-6-methoxy-5-(4-nitrophenoxy)-3-isoquinolinecarboxylic    acid, methyl ester;-   5-(4-Aminophenoxy)-2-(diphenylacetyl)-1,2,3,4-tetrahydro-6-methoxy    3-isoquinoline carboxylic acid, methyl ester;-   5-(4-Aminophenoxy)-2-(diphenylacetyl)-1,2,3,4-tetrahydro-6-methoxy-3-isoquinoline    carboxylic acid; and-   (+)-2-(Diphenylacetyl)-1,2,3,4    tetrahydro-6-methoxy-5-(phenylmethoxy)-3-isoquinoline carboxylic    acid (PD-126,055).

Certain compounds according to formula (Ic) can exist in unsolvatedforms as well as in solvated forms, including hydrated forms. Ingeneral, the solvated forms, including hydrated forms, are equivalent tounsolvated forms and are intended to be encompassed within the scope ofthe present invention.

In other embodiments, the AT₂ receptor antagonist is selected fromN,N-diacylpiperazine compounds as described for example in U.S. Pat. No.5,292,726 and especially in the compound claims of this patent.Representative examples of such compounds are represented by the formula(Ha):

or their pharmaceutically compatible salts,

wherein:

wherein: R^(1a) is

1) H,

2) C₁₋₈ alkyl.

3) phenyl, either unsubstituted or substituted with one or twosubstituents selected from:

a) —C₁₋₄ alkyl,

b) -halo,

c) —OH,

d) —CF3

e) —NH₂,

f) —NH(C₁₋₄ alkyl).

g) —N(C₁₋₄ alkyl)₂,

h) —CO₂H,

i) —CO₂ (C₁₋₄ alkyl), and

j) —C₁₋₄ alkoxy; or

4) C₁₋₄ alkyl-phenyl, wherein the phenyl is either unsubstituted orsubstituted with one or two substituents selected from:

a) —C₁₋₄ alkyl,

b) -halo,

e) —OH,

d) —CF₃

e) —NH₂,

f) —NH(C₁₋₄ alkyl),

g) —N(C₁₋₄ alkyl)₂,

h) —CO₂H,

i) —CO₂(C₁₋₄ alkyl), and

j) —C₁₋₄ alkoxy;

R^(1b) is

1) R^(1a),

2) —C₃₋₇ cycloalkyl, or

3) —CH₂—R^(1a);

R^(2a) and R^(2b) are independently phenyl, either unsubstituted orsubstituted with one or two substituents selected from:

1) —C₁₋₄ alkoxy,

2) -halo,

3) —OH,

4) CF₃,

5) —NH₂,

6) —NH(C₁₋₄ alkyl),

7) —N(C₁₋₄ alkyl)₂,

8) CO₂H,

9) —CO₂(C₁₋₄ alkyl), and

10) C₁₋₆ alkyl, either unsubstituted or substituted with:

a) -halo,

b) —OH,

c) —CF₃,

d) —NH₂,

e) —NH(C₁₋₄ alkyl),

f) —N(C₁₋₄ alkyl)₂,

g) —CO₂H,

h) —CO₂(C₁₋₄ alkyl),

i) —C₁₋₄ alkoxy,

j) —S(O)_(x)(C₁₋₄ alkyl) wherein x is 0, 1 or 2,

k) —C₃₋₇ cycloalkyl;

and the phenyl groups of R^(2a) and R^(2b) may be joined together at theortho carbon atoms through a carbon-carbon single bond or C₁₋₃ alkyleneto form a tricyclic group with the X² to which they are attached;

X¹ is —N, —CH or O, and if X¹ is O, R^(1a) is absent;

X² is —N or —CH;

R³ is

1) —C₁₋₄ alkyl,

2) —CO₂R⁶,

3) —CH₂OCOR⁶,

4) —CH₂OH,

5) —CH₂OR⁵,

6) —CH₂S(O)_(x)R⁵,

7) —CH₂OCONR⁵R⁶,

8) —CH₂CONR⁵R⁶,

9) —CONR⁵R⁶,

10) —CO₂R⁸,

11) —CH₂CO₂R⁶,

12) —CH₂CO₂R⁸,

13) —CONHSO₂R⁹

14) —CH₂N(R⁶)CONR⁵R⁶,

15) —CH₂NH₂,

16) —CH₂NH(C₁₋₄ alkyl), or

17) —CH₂N(C₁₋₄ alkyl)₂; wherein

R⁵ is C₁₋₆ alkyl either unsubstituted or substituted with:

1) -halo,

2) —OH,

3) —CF₃,

4) —NH₂,

5) —NH(C₁₋₄ alkyl),

6) —N(C₁₋₄ alkyl)₂,

7) —CO₂H,

8) —CO₂(C₁₋₄ alkyl),

9) —C₃₋₇ cycloalkyl, or

10) phenyl, either unsubstituted or substituted with

-   -   a) —C₁₋₄ alkyl,    -   b) -halo,    -   c) —OH,    -   d) —CF₃,    -   e) —NH₂,    -   f) —NH(C₁₋₄ alkyl),    -   g) —N(C₁₋₄ alkyl)₂,    -   h) —CO₂H, or    -   i) —CO₂(C₁₋₄ alkyl);

R⁶ is —H or C₁₋₄ alkyl; or

R⁵ and R⁶ can be joined together to form with the nitrogen to which theyare attached —N(CH₂CH₂)₂L; wherein L is:

-   -   i) a single bond,    -   ii) —CH₂—,    -   iii) —O—,    -   iv) —S(O)_(p)—, or    -   v) —NR⁷;

R⁷ is

1) —H,

2) —C₁₋₆ alkyl, unsubstituted or substituted with —OH, C₁₋₄ alkoxy or—N(C₁₋₄ alkyl)₂,

3) -aryl, or

4) —CH₂-aryl;

R⁸ is

1) —H,

2)

wherein:

R¹⁰ is

-   -   a) —C₁₋₆ alkyl,    -   b) -aryl, or    -   c) —CH₂-aryl,

3) —CH₂-aryl,

R⁹ is

1) -aryl,

2) -heteroaryl,

3) —C₃₋₇cycloalkyl,

4) -polyfluoro C₁₋₄ alkyl

5) —C₁₋₆alkyl, either unsubstituted or substituted with

-   -   a) -aryl,    -   b) -heteroaryl,    -   c) —OH,    -   d) —SH,    -   e) —C₁₋₄alkyl,    -   f) —C₃₋₇cycloalkyl,    -   g) —C₁₋₄alkoxy,    -   h) —C₁₋₄alkylthio,    -   i) —CF₃,    -   j) -halo,    -   k) —NO₂,    -   l) —CO₂R⁶    -   m) —N(R⁶)₂, wherein the R⁶ groups are the same or different,    -   n) —NH-aryl,    -   o) —N(aryl)₂,    -   p) —PO₃H,    -   q) —PO(OH)(OC₁₋₄alkyl) or    -   r) —N(CH₂CH₂)₂L wherein L is as defined above, and

R⁴ is H or R³.

In some embodiments, the compounds according to formula (IIa) are thosewherein X¹ and X² are both N. An illustrative class of compounds withinthese embodiments includes those compounds wherein:

R^(1a) and R^(1b) are independently H, C₁₋₈ alkyl or phenyl, eitherunsubstituted or substituted with —Cl, —Br, —I, —F, C₁₋₄ alkyl, or C₁₋₄alkoxy: and

R³ is —CO₂R⁶, or C₁₋₄alkyl; and

R⁴ is H or R³.

Specific compounds within this class include:

-   1)    1-(N,N-diphenylcarbamoyl)-4-(N,N-di-n-pentylcarbamoyl)piperazine-2-carboxylic    acid;-   2) methyl    1-(N,N-diphenylcarbamoyl)-4-(N,N-di-n-pentylcarbamoyl)piperazine-2-carboxylate;-   3) 1,4-bis(N,N-diphenylcarbamoyl)piperazine-2-carboxylic acid    (L-159,686);-   4) 1,4-bis(N,N-diphenylcarbamoyl)-2-methylpiperazine;-   5)    1-(N,N-di-n-pentylcarbamoyl)-4-(N,N-diphenylcarbamoyl)piperazine-2-carboxylic    acid;-   6)    1-(N-n-pentyl-N-phenylcarbamoyl)-4-(N,N-diphenylcarbamoyl)piperazine-2-carboxylic    acid;-   7)    1-[N-(3-chlorophenyl)-N-phenylcarbamoyl]-4-(N,N-di-n-pentylcarbamoyl)piperazine-2-carboxylic    acid;-   8)    1-[N-(3-bromophenyl)-N-phenylcarbamoyl]-4-(N,N-di-n-pentylcarbamoyl)piperazine-2-carboxylic    acid;-   9) 1,4-bis(N,N-diphenylcarbamoyl)-trans-2,5-dimethyl-piperazine;-   10)    1,4-bis[N-(3-chlorophenyl)-N-phenylcarbamoyl]-2,5-dimethyl-piperazine;    and-   11) 1,4-bis[-N-(3-chlorophenyl)-N-phenylcarbamoyl]-2,5-transdimethyl    piperazine.

Another class of compounds within these embodiments includes thosecompounds wherein:

R^(1a) and R^(1b) are independently H, C₁₋₈ alkyl or phenyl, eitherunsubstituted or substituted with —Cl, —Br, —I, —F, C₁₋₄ alkyl, orC₁₋₄alkoxy;

R³ is CONR⁵R⁶;

R⁴ is H or R³;

R⁵ is C₁₋₆ alkyl either unsubstituted or substituted with:

1) -halo,

2) —OH,

3) —CF₃,

4) —NH₂,

5) —NH(C₁₋₄alkyl),

6) —N(C₁₋₄alkyl)₂,

7) —CO₂H,

8) —CO₂(C₁₋₄alkyl),

9) —C₃₋₇ cycloalkyl, or

10) phenyl, either unsubstituted or substituted with

-   -   a) —C₁₋₄alkyl,    -   b) -halo,    -   c) —OH,    -   d) —CF₃,    -   e) —NH₂,    -   f) —NH(C₁₋₄alkyl),    -   g) —N(C₂₋₄alkyl)₂,    -   h) —CO₂H, or    -   i) —CO₂(C₂₋₄alkyl); and

R⁶ is H or C₁₋₄alkyl.

Specific compounds within this class include:

-   1)    2-[(2-carboxyethyl)aminocarbonyl]-1-(N,N-diphenylcarbamoyl)-4-(N,N-di-n-pentylcarbamoyl)-piperazine;-   2)    2-[(2-(t-butylcarboxyethyl)aminocarbonyl]-1-(N,N-diphenylcarbamoyl)-4-(N,N-di-n-pentylcarbamoyl)piperazine;-   3)    2-[(3-(N,N-diethylamino)propyl)-N-methylaminocarbonyl]-1-(N,N-diphenyl-carbamoyl)-4-(N,N-di-n-pentylcarbamoyl)-piperazine;-   4)    2-[(2-(N,N-dimethylamino)ethyl)-N-methylaminocarbonyl]-1-(N,N-diphenyl-carbamoyl)-4-(N,N-di-n-pentylcarbamoyl)-piperazine;-   5)    2-[(2-(N,N-di(1-methylethyl)amino)ethyl)aminocarbonyl]-1-(N,N-diphenylcarbamoyl)-4-(N,N-di-n-pentyl-carbamoyl)piperazine;-   6)    2-[(3-carboxypropyl)-N-methyl-aminocarbonyl]-1-(N,N-diphenylcarbamoyl)-4-(N,N-di-n-pentyl-carbamoyl)piperazine;-   7)    2-[(3-(N,N-Diethylamino)propyl)aminocarbonyl]-4-(N,N-di-n-pentylcarbamoyl)-1-(N,N-diphenylcarbamoyl)piperazine;-   8)    2-[(4-(N,N-Diethylamino)butyl)aminocarbonyl]-4-(N,N-di-n-pentylcarbamoyl)-1-(N,N-diphenylcarbamoyl)piperazine;-   9)    2-[(2-Aminoethyl)aminocarbonyl]-4-(N,N-di-n-pentylcarbamoyl)-1-(N,N-diphenylcarbamoyl)piperazine;-   10)    1-[N-(3-Chlorophenyl)-N-phenylcarbamoyl]-2-[(3-(N,N-diethylamino)propyl)aminocarbonyl]-4-(N,N-di-n-pentylcarbamoyl)piperazine;-   11)    1,4-Bis[N-(3-chlorophenyl)-N-phenylcarbamoyl]-2-[(3-(N,N-diethylamino)propyl)aminocarbonyl]piperazine;-   12)    1-[N-(3-Chlorophenyl)-N-phenylcarbamoyl]-2-[(4-(N,N-diethylamino)butyl)aminocarbonyl]-4-(N,N-di-n-pentylcarbamoyl)piperazine;-   13)    2-[(3-(N,N-Diethylamino)propyl)aminocarbonyl]-4-(N,N-di-n-pentylcarbamoyl)-1-[N-(3-methylphenyl)-N-phenylcarbamoyl]piperazine;-   14)    1-[N-(3-Chlorophenyl)-N-phenylcarbamoyl]-2-[(2-(N,N-diethylamino)ethyl)aminocarbonyl]-4-(N,N-di-n-pentylcarbamoyl)piperazine;-   15)    2-[(2-(N,N-Diethylamino)ethyl)aminocarbonyl]-4-(N,N-di-n-pentylcarbamoyl)-1-(N,N-diphenylcarbamoyl)-piperazine;-   16)    2-[(4-(N,N-Diethylamino)butyl)aminocarbonyl]-1-[N-(3,5-dimethylphenyl)-N-phenylcarbamoyl]-4-(N,N-di-n-pentylcarbamoyl)piperazine;-   17)    1-[N-(3-Chlorophenyl)-N-phenylcarbamoyl]-2-[(3-(N,N-diethylamino)propyl)aminocarbonyl]-4-(N,N-diphenylcarbamoyl)piperazine;-   18)    2-[(3-(N,N-Dimethylamino)propyl)aminocarbonyl]-4-(N,N-di-n-pentylcarbamoyl)-1-(N,N-diphenylcarbamoyl)piperazine;-   19)    2-[(3-(N,N-Diethylamino)propyl)aminocarbonyl]-1-[N-(3,5-dimethylphenyl)-N-phenylcarbamoyl]-4-(N,N-di-n-pentylcarbamoyl)piperazine;-   20)    2-[(2-(N,N-Dimethylamino)ethyl)aminocarbonyl]-4-(N,N-di-n-Pentylcarbamoyl)-1-(N,N-diphenylcarbamoyl)piperazine;-   21)    2-[(2-(N-Methylamino)ethyl-N-methyl-aminocarbonyl]-4-(N,N-di-n-pentylcarbamoyl)-1-(N,N-di-n-diphenylcarbamoyl)-piperazine;-   22)    2-[(3-(N,N-diethylamino)propyl)-aminocarbonyl]-1-[N-(3-methoxyphenyl)-N-phenylcarbamoyl]-4-(N,N-di-n-pentylcarbamoyl)-piperazine;-   23)    2-[(2-(N,N-diethylamino)ethyl)-N-(2-hydroxyethyl)aminocarbonyl]-4-(N,N-di-n-pentylcarbamoyl)-1-(N,N-diphenylcarbamoyl)piperazine;-   24)    2-[(3-(N,N-diethylamino)propyl)-aminocarbonyl]-1-[N-(4-hydroxyphenyl)-N-phenylcarbamoyl]-4-(N,N-di-n-pentylcarbamoyl)piperazine,    and-   25)    2-[(2-(N,N-diethylamino)ethyl)-(N-(2-hydroxy)ethyl)aminocarbonyl]-1-[N-(3-chlorophenyl)-N-phenylcarbamoyl]-4-(N,N-di-n-pentyl-carbamoyl)-piperazine.

Within these compounds it is preferred that the substituent at the Zposition be of the (S) stereochemical designation.

In some embodiments, the compounds according to formula (Ha) are thosewherein X¹ and X² are both CH. An illustrative class of compounds withinthese embodiments includes those compounds wherein:

R^(1a) and R^(1b) are independently H, C₁₋₈ alkyl or phenyl, eitherunsubstituted or substituted with —Cl, —Br, —I, —F, C₁₋₄alkyl, or C₁₋₄alkoxy; and

R³ is —CO₂R⁶, C₁₋₄alkyl; and

R⁴ is H or R³,

Specific compounds within this class include:

-   1) 1-diphenylacetyl-4-(3,4-dimethoxyphenylacetyl)-Z-hydroxymethyl    piperazine; and-   2)    1-diphenylacetyl-4-(3,4-dimethoxyphenylacetyl)piperazine-2-carboxylic    acid.

In some embodiments, the compounds according to formula (IIa) are thosewherein X¹ is N and X² is CH. An illustrative class of compounds withinthese embodiments includes those compounds wherein:

R^(1a) and R^(1b) are independently H, C₁₋₈alkyl or phenyl, eitherunsubstituted or substituted with —Cl, —Br, —I, —F, C₁₋₄alkyl, orC₁₋₄alkoxy; and

R³ is CO²R⁶, or C₁₋₄alkyl; and

R⁴ is H or R³.

Specific compounds within this class include:

-   1)    1-diphenylacetyl-4-(N,N-di-n-pentylcarbamoyl)piperazine-2-carboxylic    acid; and-   2)    methyl-1-diphenylacetyl-4-(N,N-di-n-pentylcarbamoyl)piperazine-2-carboxylate.

In some embodiments, the compounds according to formula (IIa) are thosewherein X¹ is CH and X² is of structural formula:

or a pharmaceutically compatible salt thereof.

An illustrative class of compounds within these embodiments are includesthose compounds wherein:

R^(1a) and R^(1b) are independently H, C₁₋₈alkyl or phenyl, eitherunsubstituted or substituted with —Cl, —Br, —I, —F, C₁₋₄alkyl, orC₁₋₄alkoxy; and

R³ is —CO₂R⁶, or C₁₋₄alkyl; and

R⁴ is H or R³.

Specific compounds within this class include:

-   1) 1-diphenylacetyl-4-(benzyloxycarbonyl)piperazine-2-carboxylic    acid.

In other embodiments, the compounds according to formula (Ha) are thosewherein X¹ is N and X² is of structural formula:

An illustrative class of compounds within these embodiments includesthose compounds wherein:

R^(1a) and R^(1b) are independently H, C₁₋₈ alkyl or phenyl, eitherunsubstituted or substituted with —Cl, —Br, —I, —F;

R^(2a) is phenyl, either unsubstituted or substituted with —Cl, —Br, —I,—F, C₁₋₄alkyl or C₁₋₄alkoxy; and

R³ is, —CO₂R⁶, or C₁₋₄alkyl; and

R⁴ is H or R³.

Specific compounds within this class include:

-   1)    1-(N,N-diphenylcarbamoyl)-4-(benzyloxycarbonyl)piperazine-2-carboxylic    acid; and-   2)    1-[N-(3-chlorophenyl)-N-phenylcarbamoyl]-4-(benzyloxycarbonyl)piperazine-2-carboxylic    acid.

In other embodiments, the AT₂ receptor antagonist is selected from theN,N-diacylpiperazine compounds listed in U.S. Pat. No. 5,348,955 andespecially in the compound claims of this patent. Representativeexamples of such compounds are represented by the formula (IIb):

or their pharmaceutically compatible salts,

wherein:

A is selected from:

R¹ is selected from the group consisting of:

1) H,

2) C₁₋₈ alkyl,

3) C₃₋₇ cycloalkyl,

4) phenyl, either unsubstituted or substituted with one or twosubstituents selected from:

-   -   a) —C₁₋₄ alkyl,    -   b) -halo,    -   c) —OH,    -   d) —CF₃    -   e) —NH₂,    -   f) —NH(C₁₋₄alkyl),    -   g) —N(C₁₋₄alkyl).sub.2,    -   h) —CO₂H,    -   i) —CO₂(C.sub₁₋₄alkyl), and    -   j) —C₁₋₄alkoxy; or

5) C₁₋₄alkyl-aryl, wherein the aryl is phenyl or naphthyl, eitherunsubstituted or substituted with one or two substituents selected from:

-   -   a) —C₁₋₄alkyl,    -   b) -halo,    -   c) —OH,    -   d) —CF₃,    -   e) —NH₂,    -   f) —NH(C₁₋₄alkyl),    -   g) —N(C₁₋₄alkyl).sub.2,    -   h) —CO₂H,    -   i) —CO₂(C₁₋₄alkyl), and    -   j) —C₁₋₄alkoxy;

R² is selected from the group consisting of:

1) —C₁₋₆ alkyl,

2) —CH₂aryl,

3) —CH₂—C₃₋₇cycloalkyl,

4) —CO₂R^(2a),

5) —CON(R^(2a)R^(2b)),

6) —SO₂N(R^(2a)R^(2b)),

7) aryl,

8) —CO-aryl, and

9) —CO—C₁₋₄alkyl;

R^(2a) and R^(2b) are independently selected from the group consistingof:

1) hydrogen,

2) —C₁₋₈alkyl,

3) —C₁₋₈alkyl-NH(C₁₋₈alkyl),

4) —C₁₋₈alkyl-NH(C₁₋₈alkyl)₂,

5) -aryl,

6) —CH₂-aryl,

or wherein —NR^(2a)R^(2b) may form a heterocyclic ring of the form—N(CH₂CH₂)₂L, wherein L is selected from the group consisting of O, S,N—C₁₋₄alkyl, N-aryl, and N—CO—C₁₋₄alkyl;

R³ is selected from the group consisting of:

1) —CO₂R^(2a),

2) —CON(R^(2a)R^(2b)),

3) —CH₂S—C₁₋₄alkyl, and

4) —CH₂O—C₁₋₄alkyl;

R⁴ is independently selected from:

1) H,

2) —C₁₋₆alkyl, and

3) —R³;

R⁵ is selected from the group consisting of:

1) hydrogen,

2) —C₁₋₆alkyl

3) —C₂₋₆alkenyl,

4) —C₂₋₄alkynyl,

5) halo,

6) —O—C₁₋₄alkyl,

7) —CF₃,

8) —CN, and

9) —CH₂O—C₁₋₄alkyl,

R⁶ is independently selected from

1) H, and

2) R⁵;

R⁷ is selected from the group consisting of:

1) —C₁₋₆alkyl

2) —C₂₋₆alkenyl,

3) —C₂₋₄alkynyl,

4) halo,

5) aryl,

6) —CH₂-aryl,

7) —O—C₁₋₄alkyl,

8) —CF₃,

9) —CN, and

10) —CH₂O—C₁₋₄alkyl;

R⁸ is selected from the group consisting of:

1) —CO₂R⁹, wherein R⁹ is hydrogen or C₁₋₆alkyl,

2) 1H-tetrazol-5-yl,

3) —CONHSO₂R¹⁰, wherein R¹⁰ is selected from:

-   -   a) —C₁₋₆ alkyl,    -   b) —C₁₋₆alkoxy,    -   c) aryl,    -   d) —CH₂aryl, and    -   e) —CH(aryl)₂,

4) —SO₂NHR¹⁰,

5) —NHSO₂R¹⁰,

6) —SO₂NHCOR¹⁰,

7) —NHSO₂CF₃, and

8) —SO₂NHCO₂R¹⁰.

The term “aryl” means phenyl or naphthyl either unsubstituted orsubstituted with one, two or three substituents selected from the groupconsisting of halo, C₁₋₄-alkyl, C₁₋₄-alkoxy, NO₂CF₃, C₁₋₄alkylthio, OH,—N(R^(2a)R^(2b), —CO₂R^(2a), C₁₋₄-perfluoroalkyl,C₃₋₆-perfluorocycloalkyl, and tetrazol-5-yl.

The term “heteroaryl” means an unsubstituted, monosubstituted ordisubstituted five or six membered aromatic heterocycle comprising from1 to 3 heteroatoms selected from the group consisting of O, N and S andwherein the substituents are members selected from the group consistingof —OH, —SH, —C₁₋₄-alkoxy, —C₁₋₄-alkoxy, —CF₃, halo, —NO₂, —CO₂R^(2a),—N(R^(2a)R^(2b)) and a fused benzo group;

The term “halo” means —Cl, —Br, —I or —F.

The term “alkyl,” “alkenyl,” “alkynyl” and the like include both thestraight chain and branched chain species of these generic terms whereinthe number of carbon atoms in the species permit. Unless otherwisenoted, the specific names for these generic terms shall mean thestraight chain species. For example, the term “butyl” shall mean thenormal butyl substituent, n-butyl.

In some embodiments, the compounds according to formula IIb arerepresented by the formula (IIbi):

or their pharmaceutically compatible salts.

Representative compounds according to formula (IIbi) include:

-   (S)-1-(Diphenylcarbamoyl)-4-N-pentyl-N-[2-(1H-tetrazol-5-yl]biphenyl-4-yl)-methyl]carbamoyl]-piperazine-2-carboxylic    acid (L-162,132);-   (S)-4-(Dipentylcarbamoyl)-1-[N-pentyl-N-[2-(1H-tetrazol-5-yl)biphenyl-4-yl)methyl]carbamoyl]-piperazine-2-carboxylic    acid;-   (S)-4-(Diphenylcarbamoyl)-1-{N-pentyl-N-[2-(1H-tetrazol-5-yl)biphenyl-4-yl)methyl]carbamoyl}-piperazine-2-carboxylic    acid;-   (S)-1-(Diphenylcarbamoyl)-4-{N-pentyl-N-[2-(1H-tetrazol-5-yl]-5-(propyl)-biphenyl-4-yl)-methyl]carbamoyl}-piperazine-2-carboxylic    acid;-   (S)-1-(Diphenylcarbamoyl)-4-{N-pentyl-N-[2-(1H-tetrazol-5-yl]-5-propyl-3-thienyl)phenyl]-methyl]carbamoyl}-piperazine-2-carboxylic    acid; and-   (S)-4-(Dipentylcarbamoyl)-1-(diphenylcarbamoyl)-piperazine-2-(3-morpholino    propyl)carboxamide.

In still other embodiments, the AT₂ receptor antagonist is selected fromthe substituted quinazolinone compounds listed in U.S. Pat. No.5,441,959 and especially in the compound claims of this patent.Representative examples of such compounds are represented by the formula(IIIa):

or a pharmaceutically compatible salt thereof,

wherein:

R¹ is —SO₂NHCO₂R²³;

R³ is

-   -   (a) halogen (Cl, Br, I, F),    -   (b) C₁-C₄ alkyl, or    -   (c) CF₃;

R⁶ is straight chain C₁-C₄ alkyl;

R⁸ is

-   -   (a) R^(23′)    -   (b) NR²⁴R^(23′);

R²³ and R^(23′) are independently

-   -   (a) aryl, wherein aryl is defined as phenyl or naphthyl        unsubstituted or substituted with one or two substituents        selected from the group consisting of: halogen (Cl, Br, I, F),        N(R²⁴)₂, CO₂R²⁴, C₁-C₄ alkyl, C₁-C₄ alkoxyl, NO₂, CF₃, C₁-C₄        alkylthio, OH, —SO₂N(R²⁴)₂, C₃-C₇ cycloalkyl, C₃-C₁₀ alkenyl and        S(O)_(n)(C₁-C₄ alkyl); where n=1 or 2,    -   (b) heteroaryl, wherein heteroaryl is an unsubstituted or mono        or disubstituted heteroaromatic 5- or 6-membered ring which can        contain one or two heteroatoms selected from the group        consisting of N, O and S and wherein the substituents are        members selected from the group consisting of —OH, —SH, C₁-C₄        alkyl, C₁-C₄ alkoxy, CF₃, halogen (Cl, Br, I, F) and NO₂,    -   (c) C₃-C₇ cycloalkyl,    -   (d) C₁-C₆ alkyl optionally substituted with a substituent        selected from the group consisting of aryl as defined above,        heteroaryl as defined above, —OH, —SH, C₁-C₄ alkyl, —O(C₁-C₄        alkyl), C₃-C₇ cycloalkyl, —S(O)_(n) (C₁-C₄ alkyl), —CF₃, halogen        (Cl, Br, F, I), —NO₂, —CO₂H, CO₂—(C₁-C₄ alkyl), —NH₂, —NH(C₁-C₄        alkyl), —N(C₁-C₄ alkyl)₂, or    -   (e) perfluoro-C₁-C₄ alkyl; and

R24 is

-   -   (a) H,    -   (b) C₁-C₆ alkyl, unsubstituted or substituted with aryl as        defined above or heteroaryl as defined above, or    -   (c) aryl; and

R^(23′) and R²⁴ when taken together may form a morpholine or piperazinering, wherein the piperazine ring may be substituted on the nitrogenwith C₁-C₄ alkyl or C₁-C₄ acyl.

One embodiment of the compounds of formula (IIIa) are those wherein:

R³ is

-   -   (a) F,    -   (b) Me, or    -   (c) CF₃;

R⁶ is straight chain C₁-C₄ alkyl;

R⁸ is R^(23′);

R^(23′) is

-   -   (a) aryl, wherein aryl is defined as phenyl or naphthyl        unsubstituted or substituted with one or two substituents        selected from the group consisting of: halogen (Cl, Br, I, F),        N(R²⁴)₂, CO₂R²⁴, C₁-C₄ alkyl, C₁-C₄ alkoxyl, NO₂, CF₃, C₁-C₄        alkylthio, OH, —SO₂N(R²⁴)₂, C₃-C₇ cycloalkyl, C₃-C₁₀ alkenyl and        S(O)_(n) (C₁-C₄ alkyl); where n=1 or 2,    -   (b) heteroaryl, wherein heteroaryl is an unsubstituted or mono-        or disubstituted heteroaromatic 5- or 6-membered ring which can        contain one or two heteroatoms selected from the group        consisting of N, O and S and Wherein the substituents are        members selected from the group consisting of —OH, —SH, C₁-C₄        alkyl, C₁-C₄ alkoxy, CF₃, halogen (Cl, Br, I, F) and NO₂,    -   (c) C₁-C₆ alkyl unsubstituted or substituted with a substituent        selected from the group consisting of aryl as defined above,        heteroaryl as defined above, —OH, —SH, C₁-C₄ alkyl, —O(C₁-C₄        alkyl), C₃-C₇ cycloalkyl, —CF₃, halogen (Cl, Br, F, I), —N(C₁-C₄        alkyl)₂, or C₃-C₇ cycloalkyl; and

R²³ is

-   -   (a) C₁-C₆-alkyl, unsubstituted or substituted with a substituent        selected from the group consisting of: aryl as defined above,        heteroaryl as defined above, C₁-C₄ alkyl, CF₃, —O(C₁-C₄ alkyl),        C₃-C₇ cycloalkyl, or    -   (b) perfluoro-C₁-C₄-alkyl.

This embodiment is exemplified further by:

R²³ R³ R⁶ R⁸ iPn F Pr Ph iPn F Pr -2-furoyl iPn F Bu Et iPn F Bu Pr iPnF Pr CH₂OCH₂CH₃ iPn F Et -2-furoyl iPn F Et Ph iPn F Et -3-pyridyl iPn FEt -4-pyridyl iPn F Et -2-pyridyl (CH₂)₂cPr F Et Ph (CH₂)₂cPr F Et-2-furoyl

wherein:

Et is ethyl,

Pr is n-propyl,

cPr is cyclopropyl,

Bu is n-butyl,

iPn is 3-methylbutyl, and

Ph is phenyl.

A second embodiment of structures of formula (IIIa) are those whereinR²³, R³, R⁶ are as recited in the first embodiment and all othersubstituents are as recited below:

R⁸ is —NR²⁴R^(23′);

R^(23′) is C₁-C₆ alkyl which is unsubstituted or substituted with asubstituent selected from the group aryl, heteroaryl, C₁-C₄ alkyl,—O(C₁-C₄ alkyl), CF₃, NH(C₁-C₄ alkyl), N(C₁-C₄ alkyl)₂, C₃-C₇cycloalkyl;

R²⁴ is

-   -   (a) C₁-C₆ alkyl which is unsubstituted or substituted with aryl        or heteroaryl, or    -   (b) H; and

R^(23′) and R²⁴ when taken together may form a morpholine or piperazinering, wherein the piperazine ring may be substituted on the nitrogenwith C₁-C₄ alkyl or C₁-C₄ acyl.

Compounds exemplifying this embodiment include:

R²³ R³ R⁶ R^(23′) R²⁴ iPn Me Pr iPr H Bu Me Pr iPr H Bu F Pr iPr H iPn FPr iPr H iPn Me Pr iPr H Bu F Bu iPr Me iPn F Pr iPr H (CH₂)₂cPr F BuiPr Me (CH₂)₂cPr F Et Et H Me F Et Et H iPn F Pr morpholino iPn F Bu iPrMe iPn F Et iPr Me iPn F Et morpholino Bu F Et morpholino iPn F Bupiperazinyl-4-methyl Bu F Et iPr Me (CH₂)₂tBu F Pr iPr H tBu F Pr iPr HiPr F Pr Me Me iHex F Et morpholino iPn F Et Me Me (CH₂)₂cPr F Et iPr H(CH₂)₂cPr F Et iPr Me L-163,579 iPn F Me iPr H iPn F Me iPr Me (CH₂)₂cPrF Me Me Me iBu F Et iPr Me iPn F Et iPr Me

wherein:

Me is methyl,

Et is ethyl,

Pr is n-propyl,

cPr is cyclopropyl,

iPr is isopropyl,

Bu is n-butyl,

iBu is isobutyl,

tBu is t-butyl,

iPn is 3-methylbutyl, and

iHex is 4-methylpentyl.

In the above embodiments described above for compounds according toformula (IIIa), the heteroaryl substituent represents any 5 or6-membered aromatic ring containing from one to three heteroatomsselected from the group consisting of nitrogen, oxygen, and sulfur, forexample, pyridyl, thienyl, furyl, pyrazolyl, pyrrolyl, imidazolyl,pyridazinyl, pyrimidinyl, pyrazinyl, isoxazolyl, isothiazolyl, oxazolyl,triazolyl and thiazolyl.

In other embodiments, the AT₂ receptor antagonist is selected from thedisubstituted 6-aminoquinazolinone compounds listed in U.S. Pat. No.5,385,894 and especially in the compound claims of this patent.Representative examples of such compounds are represented by the formula(IVa):

or a pharmaceutically compatible salt thereof,

wherein:

R¹ is

-   -   (a) CO₂R²,    -   (b) tetrazol-5-yl,    -   (c) NHSO₂CF₃,    -   (d) SO₂NHCOR³, or    -   (e) SO₂NH-heteroaryl;

R² is

-   -   (a) hydrogen, or    -   (b) C₁-C₆ alkyl;    -   R³ is    -   (a) C₁-C₆ alkyl,    -   (b) C₃-C₇ cycloalkyl,    -   (c) phenyl,    -   (d) substituted phenyl in which the substituent is F, Cl, Br,        C₁-C₄ alkoxy, perfluoro C₁-C₄ alkyl, di-(C₁-C₄-alkyl)amino, or        CO₂R²,    -   (e) substituted C₁-C₈ alkyl in which the substituent is C₃-C₇        cycloalkyl, C₁-C₄ alkoxy, hydroxy, di-(C₁-C₄ alkyl)amino, CO₂R₂,        morpholinyl, C₁-C₄ alkylpiperazinyl, CF₃, thio, C₁-C₄        alkylsulfinyl, C₁-C₄ alkylsulfonyl, heteroaryl, NH₂, or aryl, or    -   (f) heteroaryl;

R⁴ is

-   -   (a) C₁-C₆ alkyl,    -   (b) substituted C₁-C₆ alkyl in which the substituent is C₃-C₇        cycloalkyl, C₁-C₄ alkoxy, hydroxy, di-(C₁-C₄ alkyl)amino, CO₂R₂,        morpholinyl, C₁-C₄ alkylpiperazinyl, CF₃, C₁-C₄ alkylthio, C₁-C₄        alkylsulfinyl, C₁-C₄ alkylsulfonyl, —CHO, O(C₂-C₃        alkyl-O—)_(n)C₁-C₃ alkyl where n=1-5, or NHCO₂(C₁-C₆-alkyl).    -   (c) C₂-C₆ alkenyl,    -   (d) phenyl C₁-C₆ alkyl,    -   (e) substituted phenyl C₁-C₆ alkyl, in which the substituent on        the phenyl group is hydroxy, C₁-C₄ alkoxy, F, Cl, I, Br, NO₂,        cyano, CO₂R², di(C₁-C₄ alkyl)amino, —Obenzyl, CF₃,        phenyl-C₁-C₄-alkoxy, C₁-C₄ alkylthio, C₁-C₄-alkylsulfinyl,        —OPO(O-benzyl)₂, or C₁-C₄ alkylsulfonyl, amino, P(O)(OH)₂, C₁-C₄        alkyl, —OPO(O—C₁-C₆ alkyl)₂, OPO(OH)₂, OCO(CH₂)₂COOH, OSO₃H, or        O(C₂-C₃ alkyl-O—)_(n) C₁-C₃ alkyl,    -   (f) heteroaryl C₁-C₆ alkyl, or    -   (g) substituted heteroaryl C₁-C₆ alkyl, in which the substituent        on the heteroaryl group is F, Cl, NO₂, CO₂R², or di-(C₁-C₄        alkyl)amino;

R⁵ is

-   -   (a) CO₂R⁷,    -   (b) CONR⁸R⁹,    -   (c) COR¹⁰,    -   (d) SO²NR⁸R⁹, or    -   (e) SO₂R¹⁰;

R⁶ is

-   -   (a) C₁-C₆ alkyl,    -   (b) substituted C₁-C₆ alkyl in which the substituent is C₃-C₇        cycloalkyl, benzyl or C₁-C₄-alkoxy,    -   (c) cyclopropyl;

R⁷ is

-   -   (a) C₁-C₆ alkyl,    -   (b) substituted C₁-C₆ alkyl in which the substituent is C₁-C₄        alkoxy, hydroxy, di(C₁-C₄ alkyl)amino, CO₂R², morpholinyl, C₁-C₄        alkylpiperazinyl, C₁-C₄ alkylsulfinyl, C₁-C₄ alkylsulfonyl, or        O(C₂-C₃ alkyl-O—)_(n) C₁-C₃ alkyl,    -   (c) phenyl C₁-C₆ alkyl,    -   (d) substituted phenyl C₁-C₆ alkyl, in which the substituent on        the phenyl group is hydroxy, C₁-C₄ alkoxy, F, Cl, NO₂, cyano,        CO₂R², di(C₁—C4 alkyl)amino, CF₃, phenyl C₁-C₄ alkoxy, C₁-C₄        alkylthio, C₁-C₄ alkylsulfinyl, C₁-C₄ alkylsulfonyl, or O(C₂-C₃        alkyl-O—)_(n) C₁-C₃ alkyl,    -   (e) heteroaryl C₁-C₆ alkyl, or    -   (f) substituted heteroaryl C₁-C₆ alkyl, in which the substituent        on the heteroaryl group is F, Cl, NO₂, CO₂R², or di-(C₁-C₄        alkyl)amino;

R⁸ is

-   -   (a) hydrogen, or    -   (b) C₁-C₅ alkyl;

R⁹ is

-   -   (a) C₁-C₆ alkyl, or    -   (b) substituted C₁-C₆ alkyl in which the substituent is C₁-C₄        alkoxy, hydroxy, di-(C₁-C₄ alkyl)amino, CO₂R², morpholinyl,        C₁-C₄ alkylpiperazinyl, C₁-C₄ alkylsulfinyl or C₁-C₄        alkylsulfonyl,    -   (c) perfluoro C₁-C₆ alkyl,    -   (d) phenyl,    -   (e) heteroaryl, or

R⁸ and R⁹ taken together are morpholino,

R¹⁰ is

-   -   (a) phenyl,    -   (b) substituted phenyl in which the substituent is F, Cl, Br, I,        C₁-C₄-alkoxy, C₁-C₄ alkyl, NO₂, cyano, OC₆H₅, CO₂R₂, di(C₁-C₄        alkylamino), CF₃, C₁-C₄ alkylthio, C₁-C₄ alkylsulfinyl, C₁-C₄        alkylsulfonyl, —OPO(OC₁-C₆-alkyl)₂, OPO(OH)₂, OPO(O-benzyl)₂,        OCO(CH₂)₂COOH, OSO₂OH, —PO(OC₁-C₆-alkyl)₂, —PO(OH)₂, OBn, or        O—(C₂-C₃alkyl-O)_(n) C₁-C₃ alkyl,    -   (c) phenyl C₁-C₆ alkyl,    -   (d) heteroaryl,    -   (e) C₁-C₆ alkyl,    -   (f) substituted C₁-C₆ alkyl in which the substituent is C₃-C₇        cycloalkyl, C₁-C₄ alkoxy, hydroxy, di-(C₁-C₄ alkyl)amino, CO₂R²,        morpholinyl, C₁-C₄ alkylpiperazinyl, CF₃, thio, C₁-C₄        alkylsulfinyl, C₁-C₄ alkylsulfonyl, imidazolyl, —N(COC₁-C₆        alkyl)piperazinyl, or N-aryl-piperazinyl    -   (g) substituted phenyl C₁-C₆ alkyl, in which the substituent on        the phenyl group is hydroxy, C₁-C₄ alkoxy, F, Cl, NO₂, cyano,        CO₂R², di(C1-C4 alkyl)amino, CF₃, phenyl C₁-C₄ alkoxy, thio,        C₁-C₄ alkylsulfinyl, or C₁-C₄-alkylsulfonyl, or    -   (h) C₃-C₇ cycloalkyl.

R¹¹ is

-   -   (a) hydrogen,    -   (b) F, Cl, Br or I    -   (c) C₁-C₄ alkyl,    -   (d) C₁-C₄ alkoxy,

R¹² is

-   -   (a) hydrogen,    -   (b) C₁-C₅ alkyl,    -   (c) phenyl,    -   (d) substituted phenyl in which the substituent is C₁-C₄ alkoxy,        F, Cl, CO₂R², di(C₁-C₄ alkyl)amino, thio, C₁-C₄ alkylsulfinyl,        C₁-C₄ alkylsulfonyl.

In some of the above embodiments, the term heteroaryl means anunsubstituted, monosubstituted or disubstituted five or six memberedaromatic ring which contains 1 to 3 heteroatoms selected from O, S, or Nand the substituents are selected from the group consisting of C₁-C₄alkyl, F, Cl, CO₂R², or di-(C₁-C₄ alkyl)amino.

The abbreviations defined in the table below are used in the specificembodiments which are illustrated in tabular form:

Table of Abbreviations Me methyl iPn isopentyl Et ethyl Hex n-hexyl Prn-propyl cHex cyclohexyl iPr isopropyl Boc butyloxycarbonyl cPrcyclopropyl Ph phenyl Bu n-butyl Bn benzyl iBu isobutyl Bz benzoyl tButertbutyl TET tetrazol-5-yl Pn n-pentyl PIP Piperazinyl

In a first specific embodiment of the compounds according to formula(IVa), R⁵ is CO₂R⁷. One class of this embodiment is represented by thecompounds of the formula (IVa) wherein:

R¹ is tetrazol-5-yl or SO₂NHCOR³ or NHSO₂CF₃

R³ is

-   -   a) phenyl,    -   b) substituted phenyl in which the substituent is F, Cl, Br, I        or C₁-C₄ alkoxy,    -   c) C₁-C₈ alkyl substituted with di-(C₁-C₄-alkyl)amino or NH₂, or    -   d) C₃-C₇-cycloalkyl;

R⁴ is

-   -   a) C₂-C₆ alkyl,    -   b) substituted C₂-C₆ alkyl in which the substituent is: CHO,        CO₂C₁-C₄ alkyl, CO₂H, OC₁-C₄ alkyl, cyclohexyl, phenyl,        NHCO₂tBu,    -   c) benzyl,    -   d) substituted benzyl in which the substituent on the phenyl        group is: F, Cl, Br, I, OH, OPO(OC₁-C₄ alkyl)₂, OPO(Obenzyl)₂,        OPO(OH)₂, —PO(OC₁-C₄ alkyl)₂, —PO(Obenzyl)₂, OPO(OH)₂, NO₂, NH₂,        N(C₁-C₄ alkyl)₂, Obenzyl,    -   e) CH₂-heteroaryl or    -   f) C₃-C₆ alkenyl;

R⁶ is

-   -   a) C₁-C₆ alkyl,    -   b) substituted C₁-C₆ alkyl in which the substituent is: -benzyl,        —C₁-C₃ alkyl, or —OC₁-C₄ alkyl, or    -   c) cyclopropyl;

R⁷ is

-   -   a) C₁-C₆ alkyl,    -   b) benzyl,    -   c) C₂-C₄ alkyl-O—C₁-C₄ alkyl or    -   d) phenyl;

R¹¹ and R¹² are hydrogen,

Illustrating the first class of this embodiment are the followingcompounds (with their Compound Number designation) of the formula (IVa):

R⁶ R¹ R⁷ R⁴ Pr TET iBu Et Bu TET iBu Bn Bu TET tBu Me Pr TET iBu Bu PrTET Et Me Pr TET iPr Me Pr TET Me Me Pr TET Bu Me Pr TET iBu Pr Pr TETiBu Allyl Pr TET iBu Pn Pr TET iBu Pn Pr TET iBu (CH₂)₃Ph Pr TET Me BnPr TET iBu Bn Pr TET Pr Bn Pr TET Bu Bn Pr TET Bn Bz Pr TET Hex Bn PrTET tBu Bn Pr TET (CH₂)₂OMe Bn Pr TET Pr CH₂cHex Pr TET Bu Bu Pr TET(CH₂)₂OEt (CH₂)₂OMe Et TET iBu Me Et TET iBu Bn iBu TET iBu Me iBu TETiBu Bn Me TET iBu Bn Me TET iBu Me Pr SO₂NHCOPh iBu Me Pr TET Et Bn PrTET Ph CH₂-2-Pyr Et TET tBu Bn Et TET Bn Bn Bu SO₂NHBz iBu Bn Pr SO₂NHBzBu Bn Pr SO₂NHCOcPr iBu Bn Pr SO₂NHCOcPr iBu Me Pr TET Pr CH₂-4-Pyr PrTET (CH₂)₂OMe Me Pr TET Pr CH₂-3-Pyr Pr TET Pr CH₂-2-Pyr Pr TET(CH₂)₂OMe CH₂-4-Pyr CH₂OMe TET iBu Me CH₂OMe TET Pr CH₂-2-Pyr Pr SO₂NHBzBn Pn Pr TET Et CH₂-2-Pyr Pr TET Pr Bn-4-NO₂ Pr TET Pr Bn-4-NH₂ Pr TETPr Bn-4-NMe₂ H TET iBu Me

In a second specific embodiment of the compounds according to formula(IVa), R⁵ is CONR⁸R⁹. One class of this embodiment is represented by thecompounds of the formula (Ha) wherein:

R¹ is tetrazol-5-yl or SO₂NHCOR³ or NHSO₂CF₃,

R³ is

-   -   a) phenyl,    -   b) substituted phenyl in which the substituent is F, Cl, Br, I        or C₁-C₄ alkoxy,    -   c) C₁-C₈ alkyl substituted with di-(C₁-C₄-alkyl)amino or NH₂, or    -   d) C₃-C₇-cycloalkyl;

R⁴ is

-   -   a) C₂-C₆ alkyl,    -   b) substituted C₂-C₆ alkyl in which the substituent is: CHO,        CO₂C₁-C₄ alkyl, CO₂H, OC₁-C₄ alkyl, cyclohexyl, phenyl, or        NHCO₂Bu,    -   c) benzyl,    -   d) substituted benzyl in which the substituent on the phenyl        group is: F, Cl, Br, I, OH, OPO(OC₁-C₄ alkyl)₂, OPO(Obenzyl)₂,        OPO(OH)₂, —PO(OC₁-C₄-alkyl)₂, —PO(Obenzyl)₂, —OPO(OH)₂, NO₂,        NH₂, N(C₁-C₄ alkyl)₂, or Obenzyl,    -   e) CH₂-heteroaryl, or    -   f) C₃-C₆ alkenyl;

R⁶ is

-   -   a) C₁-C₆ alkyl,    -   b) substituted C₁-C₆ alkyl in which the substituent is: -benzyl,        —C₁-C₃ alkyl, or —OC₁-C₄ alkyl, or    -   c) cyclopropyl;

R⁸ is

-   -   a) C₁-C₆ alkyl or    -   b) hydrogen;

R⁹ is

-   -   a) C₁-C₆ alkyl, or    -   b) when taken with R⁸ and the nitrogen atom to which they are        attached from a morpholinyl, N—(C₁-C₆ alkyl)piperazinyl,        N—(COC₁-C₆ alkyl)piperazinyl, or N-aryl-piperazinyl ring system,

R¹¹ and R¹² are hydrogen.

Illustrating the first class of this second embodiment are the followingcompounds (with their Compound Number designation) of the formula (IVa):

R⁶ R¹ N(R⁸)R⁹ R⁴ Bu TET N(Me)iPr Me Pr TET N(Pn)₂ Me Pr TET N(Me)Pr BnPr TET N(Me)Et Bn Pr TET morpholino Bn Et TET NHPr Bn Pr TET N(Me)iPrBn-4-F Pr TET N(Me)iPr CH₂-2-Pyr

In a third specific embodiment of the compounds of the formula (IVa), R⁵is COR¹⁰. One class of this embodiment is represented by the compoundsof the formula (IVa) wherein:

R¹ is tetrazol-5-yl, SO₂NHCOR³ or NHSO₂CF₃;

R³ is

-   -   a) phenyl,    -   b) substituted phenyl in which the substituent is F, Cl, Br, I        or C₁-C₄ alkoxy,    -   c) C₁-C₈ alkyl substituted with di-(C₁-C₄ alkylamino or NH₂, or    -   d) C₃-C₇-cycloalkyl;

R⁴ is

-   -   a) C₂-C₆ alkyl,    -   b) substituted C₂-C₆ alkyl in which the substituent is: CHO,        CO₂C₁-C₄ alkyl, CO₂H, OC₁-C₄ alkyl, cyclohexyl, phenyl, or        NHCO₂tBu,    -   c) benzyl,    -   d) substituted benzyl in which the substituent on the phenyl        group is: F, Cl, Br, I, OH, OPO(OC₁-C₄ alkyl)₂, OPO(Obenzyl)₂,        OPO(OH)₂, —PO(OC₁-C₄ alkyl)₂, —PO(Obenzyl)₂, OPO(OH)₂, NO₂, NH₂,        N(C₁-C₄ alkyl)₂, Obenzyl, OC₁-C₄ alkyl, COOH, or CO₂CH₃,    -   e) CH₂-heteroaryl or    -   f) C₃-C₆ alkenyl;

R⁶ is

-   -   a) C₁-C₆ alkyl,    -   b) substituted C₁-C₆ alkyl in which the substituent is: -benzyl,        —C₁-C₃ alkyl, or —OC₁-C₄ alkyl or    -   c) cyclopropyl;

R¹⁰ is

-   -   (a) phenyl,    -   (b) substituted phenyl in which the substituent is F, Cl, Br, I,        methoxy, methyl, CF₃, SMe, SO₂Me, OH, OPO(O—C₁-C₄ alkyl)₂,        OPO(OH)₂, OPO(OBn)₂, CO₂C₁-C₄ alkyl, COOH, Obenzyl or OC₆H₅,    -   (c) benzyl,    -   (d) heteroaryl,    -   (e) C₁-C₆ alkyl or    -   (f) substituted C₁-C₆ alkyl substituted with: imidazole,        piperazine, morpholinyl, N—(C₁-C₆ alkyl) piperazinyl, N—(COC₁-C₆        alkyl) piperazinyl, or N-aryl-piperazinyl;

R¹¹ and R¹² are hydrogen.

Illustrating the first class of this third embodiment are the followingcompounds (with their Compound Number designation) of the formula (IVa):

R⁶ R¹ R¹⁰ R⁴ Pr TET Ph Pn Pr TET Bn Pn Pr TET 4-Pyr Pn Pr TET Ph Bn PrTET Ph-4-Cl Pn Pr TET Ph-4-Cl Pn Pr TET Ph-4-Ome 4-Methyl- pentyl Pr TET2-Furyl Pn Pr TET 3-methyl- butyl Pr TET Bu Bn Pr TET Ph-4-F Pn Pr TETPh-4-F Bu Pr TET Ph-4-Me Pn Pr TET Ph-3-Br Pn Pr TET 3-Methyl- Bn-4-OHbutyl Pr TET Bu Bu Et TET Ph Bn Pr TET Ph-4-CF₃ Pn Et TET Ph-4-F Pn1-Methyl- TET Ph-4-F Pn pentyl Et TET Ph-4-F Bu Et TET Ph Bn-4-F cPr TETPh Bn cPr TET Ph Pn 1-Methyl-3- TET Ph Bn phenethyl cPr TET Ph Bn cPrTET Ph Bn Pr TET 4-Py Bu Me TET Ph Bn iPr TET Ph Bn Et SO₂NHBz Ph Bn PrTET 3-Pyr Pn Pr SO₂NHCOcPr Ph Pn Pr SO₂NHBz Ph Pn Et TET 4-Pyr Bn Pr TETPh-4-SMe Pn Pr TET Ph Pr Et TET Ph-2-Cl Bn Et TET Ph-2-Cl Bn-2-Cl Pr TETPh-4-SOMe Pn Pr TET Ph (CH₂)CHO Pr TET Ph-4-SO2Me Pn Et TET Ph Bn-2-ClEt TET Ph CH₂CH═CMe₂ Pr SO₂NHCOcPr Me Pr Pr SO₂NHCOcPr cPr Pn PrSO₂NHCOcPr Me Pn Pr SO₂NHCOPh cPr Pr Pr TET Ph-4-F Pr Et TET Ph iPn iPrTET Ph Bn-2-Cl iPr TET cPr Bn iPr TET cPr Bn-2-Cl H TET Ph Bn H TET PhBn-2-Cl Et TET Ph Bn-4-Cl Et TET Ph Bn-4-F Et TET Ph Bn-3-Et 1-ethyl-TET Ph Bn ethyl 1-ethyl- TET Ph Bn-2-Cl ethyl Pr TET Ph iBu Pr TET Ph(CH₂)₃CO₂Et Pr NHSO₂CF₃ Ph Pn Pr TET Ph (CH₂)₃CO₂H Me TET Ph Bn-2-Cl MeTET 4-Pyr Bn Pr SO₂NHCOcPr Me Me Pr TET Ph CH₂CO₂Et Me TET 4-Pyr Bn-2-ClMe TET 4-Pyr CH₂CH═CMe₂ Et TET Ph Bn-4-I Pr TET 2-thienyl Pn Pr TET2-thienyl Me iPr TET Ph Bn-4-I Et TET Ph-4-I Bn Et TET Ph Bz-2-I Et TET2-thienyl Bn (L-161,638) Pr TET 4-Pyr (CH₂)₂)OMe Pr TET Ph CH₂CO₂HCH₂OMe TET Ph-4-Cl Pn Et TET 2-furoyl Bn Pr TET 2-thienyl Bn Pr TET2-thienyl Et Pr TET 2-furoyl Et Pr TET Ph-2-OMe Bn Pr TET Ph-2-OMe Pr PrTET Ph-4-OBn Pn Pr TET Ph-4-OBn Pr Pr TET Ph-4-OH Pn Pr TET Ph-4-OH PrPr TET CH₂imidazole Bn Pr TET CH₂PIPBoc Bn Pr TET 3-Pyr Bn Pr TET 2-PyrBn Pr TET Ph CH₂-2-Pyr Pr TET Ph CH₂-4-Pyr Pr TET 4-Pyr Bn Pr TET 2-PyrBn Pr TET Ph CH₂-3-Pyr Pr TET Ph CH₂-2-Pyr Pr TET Ph-4-OPO(OBn)₂ Pn PrTET Ph-4-OH Bu Pr TET 4-Pyr CH₂-2-Pyr Pr TET Ph-4-OP(OH)₂ Pn Pr TETPh-4-OH Bn Pr TET 2-furoyl CH₂-2-Pyr Pr TET Ph-4-OPO(ONa)₂ Bu

In a fourth embodiment of the compounds of the formula (IVa), R⁵ isSO₂R¹⁰. One class of this embodiment is represented by the compounds ofthe formula (IVa) wherein:

R¹ is tetrazol-5-yl, SO₂NHSO₂CF₃ or NHSO₂CF₃

R³ is

-   -   (a) phenyl,    -   (b) substituted phenyl in which the substituent is F, Cl, Br, I        or C₁-C₄ alkoxy,    -   (c) C₁-C₈ alkyl substituted with di-(C₁-C₄ alkyl)amino or NH₂,        or    -   (d) C₃-C₇-cycloalkyl;

R⁴ is

-   -   (a) C₂-C₆ alkyl,    -   (b) substituted C₁-C₆ alkyl in which the substituent is: CHO,        CO₂C₁-C₄ alkyl, CO₂H, OC₁-C₄ alkyl, cyclohexyl, phenyl, or        NHCO₂tBu,    -   (c) benzyl,    -   (d) substituted benzyl in which the substituent on the phenyl        group is: F, Cl, Br, I, OH, OPO(OC₁-C₄ alkyl)₂, OPO(Obenzyl)₂,        OPO(OH)₂, —PO(OC₁-C₄ alkyl)₂, —PO(Obenzyl)₂, —OPO(OH)₂, NO₂,        NH₂, N(C₁-C₄ alkyl)₂, or Obenzyl,    -   (e) CH₂-heteroaryl or    -   (f) C₃-C₆ alkenyl;

R⁶ is

-   -   (a) C₁-C₆ alkyl,    -   (b) substituted C₁-C₆ alkyl in which the substituent is:        -benzyl, —C₁-C₃ alkyl, or —OC₁-C₄ alkyl or,    -   (c) cyclopropyl;

R¹⁰ is

-   -   (a) phenyl,    -   (b) substituted phenyl in which the substituent is F, Cl, Br, I,        methoxy, methyl, CF₃, SMe, SOMe, SO₂Me, OH, OPO(O—C₁-C₄ alkyl)₂,        OPO(OH)₂, OPO(OBn)₂, CO₂C₁-C₄ alkyl, or COOH,    -   (c) benzyl,    -   (d) heteroaryl,    -   (e) C₁-C₆ alkyl, or    -   (f) substituted C₁-C₆ alkyl substituted with: imidazole,        piperazine, morpholinyl, N—(C₁—C alkyl)-piperazinyl, N—(COC₁-C₆        alkyl)-piperazinyl, or N-aryl-piperazinyl;

R¹¹ and R¹² are hydrogen.

Illustrating this class of the fourth embodiment is the followingcompounds (with its Example Number designation) of the formula (IVa):

R⁶ R¹ R¹⁰ R⁴ Pr TET Bu Bn Et TET Pr Pn Et TET Bu Pn Et TET Pr(CH₂)₃NHBoc Et TET Pr Bn

In still other embodiments, the AT₂ receptor antagonist is selected fromthe imidazole compounds listed in U.S. Pat. No. 5,545,651 and especiallyin the compound claims of this patent. Representative examples of suchcompounds are represented by the formula (VI):

wherein:

R′ is in the meta or para position and is

-   -   (a) 4-CO₂H,    -   (b) —CH₂CO₂H,    -   (c) —C(CF₃)₂OH,    -   (d) —CONHNHSO₂CF₃,    -   (e) 4-CONHCH(CO₂H)CH₂C₆H₅ (L-isomer),    -   (f) 4-CONHOR¹²,    -   (g) —CONHSO₂R¹⁰,    -   (h) —CONHSO₂NHR⁹,    -   (i) —C(OH)R⁹PO₃H₂,    -   (j) —NHCOCF₃,    -   (k) —NHCONHSO₂R¹⁰,    -   (l) —NHPO₃H₂,    -   (m) 4-NHSO₂R¹⁰,    -   (n) —NHSO₂NHCOR¹⁰,    -   (o) —OPO₃H₂,    -   (p) —OSO₃H,    -   (q) —PO₃H₂,    -   (r) —PO(OH)R⁹,    -   (s) —SO₃H,    -   (t) —SO₂NHR⁹,    -   (u) —SO₂NHCOR¹⁰,    -   (v) —SO₂NHCONHR⁹,

-   -   (ii) —SO₂NHCO₂R¹⁰;

R² is independently

-   -   (a) H,    -   (b) halo (F, Cl, Br, I),    -   (c) C1-4-alkyl,    -   (d) C1-4-alkoxy,    -   (e) C1-4-acyloxy,    -   (f) C1-4-alkylthio,    -   (g) C1-4-alkylsulfinyl,    -   (h) C1-4-alkylsulfonyl,    -   (i) —(C1-4-alkyl)-OH,    -   (j) —(C1-4)alkyl-aryl,    -   (k) —CO2H,    -   (l) —CN,    -   (m) tetrazol-5-yl,    -   (n) —CONHOR12,    -   (o) —SO2NHR9,    -   (p) —NH2,    -   (q) C1-4-alkylamino,    -   (r) C1-4-dialkylamino,    -   (s) —NHSO2R10,    -   (t) —NO2,    -   (u) furyl,    -   (v) phenyl or phenyl optionally substituted with one or two        substituents selected from the group consisting of halo,        C1-4-alkyl, C1-4-alkoxy, —NO2, —CF3, C1-4-alkylthio, —OH, —NH2,        C1-4-alkylamino, C1-4-dialkylamino, —CN, —CO12R12, acetyl;

R³ is independently

-   -   (a) H,    -   (b) halo,    -   (c) C₁₋₄-alkyl,    -   (d) C₁₋₄-alkoxy, or    -   (e) —C₁₋₄-alkyl-(C₁-C₄-alkoxy);

R⁴ is

-   -   (a) —CN,    -   (b) —NO₂, or    -   (c) —CO₂R¹¹;

R⁵ is

-   -   (a) H,    -   (b) C₁₋₆-alkyl,    -   (c) C₃₋₆-cycloalkyl,    -   (d) C₂₋₄-alkenyl, or    -   (e) C₂₋₄-alkynyl;

R⁶ is

-   -   (a) C₁₋₁₀-alkyl,    -   (b) C₁₋₁₀-alkenyl,    -   (c) C₃₋₁₀-alkynyl,    -   (d) C₃₋₈-cycloalkyl,    -   (e) C₃₋₄-cycloalkenyl,    -   (f) —C₁₋₃-alkyl-(C₃-C₈-cycloalkyl),    -   (g) —C₁₋₃-alkenyl-(C₅-C₁₀-cycloalkyl),    -   (h) —C₁₋₃-alkynyl-(C₅-C₁₀-cycloalkyl),    -   (i) —(CH₂)_(s) S(CH₂)_(m)R⁵, or    -   (j) benzyl, optionally substituted on the phenyl ring with 1-2        substituents selected from the group consisting of halo,        C₁₋₄-alkyl, C₁₋₄-alkoxy or —NO₂;

R⁷ is

-   -   (a) C₁₋₆-alkyl,    -   (b) C₃₋₆-cycloalkyl,    -   (c) aryl, or    -   (d) benzyl, optionally substituted on the phenyl ring with 1-2        substituents selected from the group consisting of halo,        C₁₋₄-alkyl, C₁₋₄-alkoxy or —NO₂;

R⁸ is

-   -   (a) H,    -   (b) halogen (F, Cl, Br, I),    -   (c) phenyl, or phenyl optionally substituted with halogen (F,        Cl, Br, I), C₁-C₄-alkyl, —OH, C₁-C₄alkoxy, —NO₂, —NR²⁶R²⁷,        —NR²⁶COR¹¹, —NR²⁶CO₂R⁷, —S(O)_(r)R¹⁰, —SO₂NR²⁶R²⁷, —NR²⁶SO₂R¹⁰,        —CF₃,    -   (d) C₁-C₆-alkyl, optionally substituted with        -   i) OR²⁵,        -   ii) S(O)_(r)R¹⁰,        -   iii) NR²³R²⁴,        -   iv) NR²⁶COR¹¹,        -   v) NR²⁶CO₂R⁷,        -   vi) NR²⁶CONR²³R²⁴,        -   vii) OCONR²³R²⁴,        -   viii) OCOR¹¹,        -   ix) aryl,    -   (e) C₂₋₆-alkenyl,    -   (f) —C₁₋₄-alkyl-aryl,    -   (h) C₁₋₄-alkoxy,    -   (i) C_(v)F_(2v+1) where v=1 to 3,    -   (j) —S(O)_(r)R¹⁰,    -   (k) —S(O)₂NR²³R²⁴,    -   (l) —CONR²³R²⁴,    -   (m) —COR⁷, or    -   (n) —CO₂R¹²;

R⁹ is

-   -   (a) H,    -   (b) C₁₋₅-alkyl    -   (c) aryl,    -   (d) —(C₁₋₄-alkyl)-aryl,    -   (e) heteroaryl, or    -   (f) C₃₋₅-cycloalkyl;

R¹⁰ is

-   -   (a) aryl,    -   (b) C₃₋₇cycloalkyl,    -   (c) C₁₋₄-perfluoroalkyl,    -   (d) C₁₋₄-alkyl, optionally substituted with a substituent        selected from the group consisting of aryl, heteroaryl, —OH,        —SH, C₁₋₄-alkyl, C₁₋₄-alkoxy, C₁₋₄-alkylthio, —CF₃, halo, —NO₂,        —CO₂R¹², —NH₂, C₁₋₄-alkylamino, C₁₋₄-dialkylamino, —PO₃H₂, or    -   (e) heteroaryl;    -   R¹¹, R^(11a), and R^(11b) are independently    -   (a) H,    -   (b) C₁₋₆-alkyl,    -   (c) C₃₋₆-cycloalkyl,    -   (d) aryl,    -   (e) —(C₁₋₆-alkyl)-aryl, or    -   (f) heteroaryl;

R¹² is

-   -   (a) H,    -   (b) methyl, or    -   (c) benzyl, optionally substituted on the phenyl ring with 1-2        substituents selected from the group consisting of halo,        C₁₋₄-alkyl, C₁₋₄-alkoxy or —NO₂;

R¹³ is

-   -   (a) —CO₂H,    -   (b) —CH₂CO₂H,    -   (c) —C(CF₃)₂OH,    -   (d) —CONHNHSO₂CF₃,    -   (e) —CONHOR¹²,    -   (f) —CONHSO₂R¹⁰,    -   (g) —CONHSO₂NHR⁹,    -   (h) —C(OH)R⁹PO₃H₂,    -   (i) —NHCOCF₃,    -   (j) —NHCONHSO₂R¹⁰,    -   (k) —NHPO₃H₂,    -   (l) —NHSO₂R¹⁰,    -   (m) —NHSO₂NHCOR¹⁰,    -   (n) —OPO₃H₂,    -   (o) —OSO₃H,    -   (p) —PO(OH)R⁹,    -   (q) —PO₃H₂,    -   (r) —SO₃H,    -   (s) —SO₂NHR⁹,    -   (t) —SO₂NHCOR¹⁰,    -   (u) —SO₂NHCONHR⁹,    -   (v) —SO₂NHCO₂R¹⁰,

R¹⁴ is

-   -   (a) H,    -   (b) C₁₋₆-alkyl,    -   (c) —CH₂CH═CH₂, or    -   (d) benzyl, optionally substituted on the phenyl ring with 1-2        substituents selected from the group consisting of halo,        C₁₋₄-alkyl, C₁₋₄-alkoxy or —NO₂;

R¹⁵ is

-   -   (a) H,    -   (b) C₁₋₈-alkyl,    -   (c) C₁₋₈perfluoroalkyl,    -   (d) C₃₋₆-cycloalkyl,    -   (e) aryl, or    -   (f) benzyl, optionally substituted on the phenyl ring with 1-2        substituents selected from the group consisting of halo,        C₁₋₄alkyl, C₁₋₄-alkoxy or —NO₂;

R¹⁶ is

-   -   (a) H,    -   (b) C₁₋₆-alkyl, or    -   (c) benzyl, optionally substituted on the phenyl ring with 1-2        substituents selected from the group consisting of halo,        C₁₋₄alkyl, C₁₋₄-alkoxy or —NO₂;

R¹⁷ is

-   -   (a) H,    -   (b) C₁₋₆-alkyl,    -   (c) C₃₋₆-cycloalkyl,    -   (d) aryl, or    -   (e) benzyl, optionally substituted on the phenyl ring with 1-2        substituents selected from the group consisting of halo,        C₁₋₄-alkyl, C₁₋₄alkoxy or —NO₂;

R¹⁸ is

-   -   (a) —NR¹⁹R²⁰,    -   (b) —NHCONH₂,    -   (c) —NHCSNH₂, or    -   (d) —NHSO₂—C₆H₅;

R¹⁹ and R²⁰ are independently

-   -   (a) H,    -   (b) C₁₋₅alkyl, or    -   (c) aryl,

R²¹ and R²² are independently

-   -   (a) C₁₋₄-alkyl,    -   or taken together are    -   (b) —(CH₂)_(q)—;

R²³ and R²⁴ are, independently

-   -   (a) H,    -   (b) C₁₋₆-alkyl,    -   (c) aryl, or    -   (d) —(C₁₋₄-alkyl)-aryl, or    -   (e) R²³ and R²⁴ when taken together constitute a pyrrolidine,        piperidine or morpholine ring;

R²⁵ is

-   -   (a) H,    -   (b) C₁₋₆-alkyl,    -   (c) aryl,    -   (d) —(C₁₋₄-alkyl)-aryl,    -   (e) C₃₋₆-alkenyl, or    -   (f) —(C₃₋₆-alkenyl)-aryl;

R²⁶ and R²⁷ are independently

-   -   (a) H,    -   (b) C₁₋₄-alkyl,    -   (c) aryl, or    -   (d) —CH₂-aryl;

R²⁸ is

-   -   (a) aryl, or    -   (b) heteroaryl;

R²⁹ is

-   -   (a) —CHO,    -   (b) —CONH₂,    -   (c) —NHCHO,    -   (d) —CO—(C₁₋₆ perfluoralkyl),    -   (e) —S(O)_(r)—(C₁₋₆ perfluoroalkyl),    -   (f) —O—(C₁₋₆ perfluoroalkyl), or    -   (g) —NR^(11a)—(C₁₋₆ perfluoroalkyl);

R³⁰ is

-   -   (a) —CHO,    -   (b) —SO₂—(C₁-C₆ perfluoroalkyl), or    -   (c) —CO—(C₁-C₆ perfluoroalkyl);

A is

-   -   (a) —(CH₂)_(n)-L¹-B-(T)_(y)-(B)_(y)—X²—(B)_(y)—R²⁸,    -   (b) —(CH₂)_(n)-L¹-B-T-(B)_(y)—R²⁸,    -   (c) —(CH₂)_(n)-L¹-B-(T)_(y)-(B)_(y)—X²—B,    -   (d) —(CH₂)_(n)-L¹-B-T-(B)_(y)—R²⁹,    -   (e) —(CH₂)_(n)-L¹-T-(B)_(y)—X² (B)_(y)—R²⁸,    -   (f) —(CH₂)_(n)-L¹-T-(B)_(y)—R²⁸,    -   (g) —(CH₂)_(n)-L¹-T-(B)_(y)—X²—B,    -   (h) —(CH₂)_(n)-L¹-(CR¹⁹R.²⁰)-D-(T)_(y)-(B)_(y)—X³—(B)_(y)—R²⁸,    -   (i) —(CH₂)_(n)-L¹-(CR¹⁹R.²⁰)-D-T-(B)_(y)—R²⁸,    -   (j) —(CH₂)_(n)-L¹-(CR¹⁹R.²⁰)-D-(T)_(y)-(B)_(y)—X³—B,    -   (k) —(CH₂)_(n)-L¹-(CR¹⁹R.²⁰)-D-T-(B)_(y)—R²⁹,    -   (l) —(CH₂)_(n)-L¹-(CR¹⁹R.²⁰)-D-T-(B)_(y)—X⁴—(B)_(y)—R²⁸,    -   (m) —(CH₂)_(n)-L¹-(CR¹⁹R.²⁰)-D-B—X⁴—(B)_(y)—R²⁸,    -   (n) —(CH₂)_(n)-L¹-(CR¹⁹R.²⁰)-D-T-(B)_(y)—X⁴—B,    -   (o) —(CH₂)_(n)-L¹-(CR¹⁹R.²⁰)-D-B—X⁴—B,    -   (p) —(CH₂)_(n)-L²-B-(T)_(y)-(B)_(y)—X²—(B)_(y)—R²⁸,    -   (q) —(CH₂)_(n)-L²-B-T-(B)_(y)—R²⁸,    -   (r) —(CH₂)_(n)-L²-B-(T)_(y)-(B)_(y)—X²—B,    -   (s) —(CH₂)_(n)-L²-B-T-(B)_(y)—R²⁹,    -   (t) —(CH₂)_(n)-L²-T-(B)_(y)—X²—(B)_(y)—R²⁸,    -   (u) —(CH₂)_(n)-L²-T-(B)_(y)—R²⁸,    -   (v) —(CH₂)_(n)-L²-T-(B)_(y)—X²—B,    -   (w) —(CH₂)_(n)-L²-D-(T)_(y)-(B)_(y)—X³—(B)_(y)—R²⁸,    -   (x) —(CH₂)_(n)-L²-D-T-(B)_(y)—R²⁸,    -   (y) —(CH₂)_(n)-L²-D-(T)_(y)-(B)_(y)—X³—B,    -   (z) —(CH₂)_(n)-L²-D-T-(B)_(y)—R²⁹,    -   (aa) —(CH₂)_(n)-L²-D-T-(B)_(y)—X⁴—(B)_(y)—R²⁸,    -   (bb) —(CH₂)_(n)-L²-D-B—X⁴—(B)_(y)—R²⁸,    -   (cc) —(CH₂)_(n)-L²-D-T-(B)_(y)—X⁴—B,    -   (dd) —(CH₂)_(n)-L²-D-B—X⁴—B,    -   (ee) —(CH₂)_(m)-L³-B-(T)_(y)-(B)_(y)—X²—(B)_(y)—R²⁸,    -   (ff) —(CH₂)_(m)-L³-B-T-(B)_(y)—R²⁸,    -   (gg) —(CH₂)_(m)-L³-B-(T)_(y)-(B)_(y)—X²—B,    -   (hh) —(CH₂)_(m)-L³-B-T-(B)_(y)—R²⁸,    -   (ii) —(CH₂)_(m)-L³-T-(B)_(y)—X²—(B)_(y)—R²⁸,    -   (jj) —(CH₂)_(m)-L³-T-(B)_(y)—R²⁸,    -   (kk) —(CH₂)_(m)-L³-T-(B)_(y)—X²—B,    -   (ll) —(CH₂)_(m)-L³-(CR⁸⁹R²⁰)-D-(T)_(y)-(B)_(y)—X³—(B)_(y)—R²⁸,    -   (mm) —(CH₂)_(m)-L³-(CR¹⁹R²⁰)-D-T-(B)_(y)—R²⁸,    -   (nn) —(CH₂)_(m)-L³-(CR¹⁹R²⁰)-D-(T)_(y)-(B)_(y)—X³—B,    -   (oo) —(CH₂)_(m)-L³-(CR¹⁹R²⁰)-D-T-(B)_(y)—R²⁹,    -   (pp) —(CH₂)_(m)-L³-(CR¹⁹R.²)-D-T-(B)_(y)—X⁴—(B)_(y)—R²⁸,    -   (qq) —(CH₂)_(m)-L³-(CR¹⁹R.²⁰)-D-(B)—X⁴—(B)_(y)—R²⁸,    -   (rr) —(CH₂)_(m)-L³-(CR¹⁹R.²⁰)-D-T-(B)_(y)—X⁴—B,    -   (ss) —(CH₂)_(m)-L³-(CR¹⁹R.²⁰)-D-B—X⁴—B,

L¹ is

-   -   (a) —CO₂—,    -   (b) —CONR^(11a)—,    -   (c) —NR^(11a)CO₂—, or    -   (d) —NR^(11a)CONR^(11b)—;

L² is

-   -   (a) —CO—,    -   (b) NR^(11a)CO—, or    -   (c) —O₂C—;

L³ is

-   -   (a) —O—,    -   (b) —SO—, or    -   (c) —NR^(11a)—;

B is C₁₋₆ alkyl;

D is C₂₋₈ alkenyl or C₂₋₈ alkynyl;

T is

-   -   (a) arylene, or    -   (b) heteroarylene

X¹ is

-   -   (a) a carbon-carbon single bond,    -   (b) —CO—,    -   (c) —C(R¹⁹)(R²⁰)—,    -   (d) —O—,    -   (e) —S—,    -   (f) —SO—,    -   (g) —SO₂—,    -   (h) —NR¹⁴—,    -   (i) —CONR¹⁶—,    -   (j) —R¹⁶CO—,    -   (k) —OC(R¹⁹)(R²⁰)—,    -   (l) —C(R¹⁹)(R²⁰)O—,    -   (m) —SC(R¹⁹)(R²⁰)—,    -   (n) —C(R¹⁹)(R²⁰)S—,    -   (o) —NHC(R¹⁹)(R²⁰)—,    -   (p) —C(R¹⁹)(R²⁰)NH—,    -   (q) —NR¹⁶SO₂—,    -   (r) —SO₂NR¹⁶—,    -   (s) —CH═CH—,    -   (t) —CF═CF—,    -   (u) —CF═CH—,    -   (v) —CH═CF—,    -   (w) —CF₂CF₂—,    -   (x) —CH(OR¹⁵)—,    -   (y) —CH(OCOR¹⁷)—,    -   (z) —C(═NR¹⁸)—,    -   (aa) —C(OR²¹)(OR²²)—,    -   (bb) 1,2-cyclopropyl, or    -   (cc) 1,1-cyclopropyl;

X² is

-   -   (a) —CO—,    -   (b) —O—,    -   (c) —S(O)_(r)—,    -   (d) —(C₁₋₄-alkylene)-,    -   (e) —NR^(11a)CONR^(11b)—,    -   (f) —CONR^(11a)—,    -   (g) —NR^(11a)CO—,    -   (h) —SO₂NR¹⁶—,    -   (i) —NR¹⁶SO₂—,    -   (j) —OCONR^(11a)SO₂—,    -   (k) —SO₂NR^(11a)CO—,    -   (l) —SO₂NR^(11a)CO—,    -   (m) —OCONR^(11a)SO₂—,    -   (n) —SO₂NR^(11a)CONR^(11b)—,    -   (o) —NR^(11a)CONR^(11b)SO₂—,    -   (p) —SO₂NR^(11a)SO₂—,    -   (q) —ONR^(11a)SO₂NR^(11b)—, or    -   (r) —NR^(11a) SO₂NR^(11b)CO—;

X³ is

-   -   (a) —C—,    -   (b) —SO—,    -   (c) —SO₂—,    -   (d) single bond,    -   (e) —CONR^(11a)—,    -   (f) —SO₂NR¹⁶—,    -   (g) —CONR^(11a)SO₂—,    -   (h) —SO₂NR^(11a)CO—,    -   (i) —SO₂NR^(11a)CO₂—,    -   (j) —SO₂NR^(11a) CONR^(11b)—,    -   (k) —SO₂NR^(11a) SO₂—, or    -   (l) —CONR^(11a) SO₂NR^(11b)—;

X⁴ is

-   -   (a) —NR^(11a)CONR^(11b)—,    -   (b) —OCONR^(11a)SO₂—,    -   (c) —NR¹⁶SO₂—,    -   (d) —OCONR^(11a)SO₂—,    -   (e) —NR^(11a)CONR^(11b)SO₂—, or    -   (f) —NR^(11a)SO₂NR^(11b)CO—;

X⁵ is

-   -   (a) —CO—,    -   (b) —SO₂—,    -   (c) —COO—, or    -   (d) —CONR^(11a)—;

Z is

-   -   (a) —O—,    -   (b) —S—, or    -   (c) —NR¹¹—;

k is 1 or 2;

m is 1 to 5;

n is 0 to 2;

q is 2 to 3;

r is 0 to 2;

s is 0 to 5;

t is 0 to 3;

u is 2 to 5;

y is 0 or 1;

and pharmaceutically compatible salts of these compounds.

In specific embodiments, the above compounds are those of formula (VI)wherein

A is

-   -   (a) —(CH₂)_(n)-L¹-S-(T)_(y)-(S)_(y)—X²—(S)_(y)—R²⁸,    -   (b) —(CH₂)_(n)-L¹-B-T-(B)_(y)—R²⁸,    -   (c) —(CH₂)_(n)-L¹-B-(T)_(y)-(B)_(y)—X²—B,    -   (d) —(CH₂)_(n)-L¹-B-T-(B)_(y)—R²⁹    -   (e) —(CH₂)_(n)-L²-B-(T)_(y)-(B)_(y)—X²—(B)_(y)—R²⁸,    -   (f) —(CH₂)_(n)-L²-B-T-(B)_(y)—R²⁸, or    -   (g) —(CH₂)_(n)-L²-B-(T)_(y)-(B)_(y)—X²—B,    -   (h) —(CH₂)_(n)-L²-B-T-(B)_(y)—R²⁹;

An illustrative example of the specific embodiments described above is acompound of formula (VIa)

wherein:

R² is independently

-   -   (a) H,    -   (b) halo (F, Cl, Br, I), or    -   (c) C₁₋₄-alkyl;

R³ is

-   -   (a) H, or    -   (b) halo (F, Cl, Br, I);

R⁶ is

-   -   (a) C₁₋₁₀ alkyl,    -   (b) C₃₋₁₀ alkenyl, or    -   (c) C₃₋₁₀ alkynyl;

R⁹ is

-   -   (a) H,    -   (b) C₁₋₅-alkyl,    -   (c) aryl,    -   (d) —(C₁₋₄-alkyl)-aryl, or    -   (e) heteroaryl;

R¹⁰ is

-   -   (a) aryl,    -   (b) C₃₋₇-cycloalkyl,    -   (c) C₁₋₄perfluoroalkyl,    -   (d) C₁₋₄-alkyl, optionally substituted with a substituent        selected from the group consisting of aryl, heteroaryl, —OH,        —SH, C₁₋₄-alkyl, C₁₋₄-alkoxy, C₁₋₄-alkylthio, —CF₃, halo, —NO₂,        —CO₂R¹², —NH₂, C₁₋₄-alkylamino, C₁₋₄-dialkylamino, —PO₃H₂, or    -   (e) heteroaryl;

R¹¹, R^(11a) and R^(11b) are independently

-   -   (a) H,    -   (b) C₁₋₆-alkyl,    -   (c) C₁₋₆-cycloalkyl,    -   (d) aryl,    -   (e) —(C₁₋₅-alkyl)-aryl, or    -   (f) heteroaryl;

R¹³ is

-   -   (a) —CO₂H,    -   (b) —CONHSO₂R¹⁰,    -   (c) —CONHSO₂NHR⁹,    -   (d) —NHCONHSO₂R¹⁰,    -   (e) —NHSO₂R¹⁰,    -   (f) —NHSO₂NHCOR¹⁰,    -   (g) —SO₂NHR⁹,    -   (h) —SO₂NHCOR¹⁰,    -   (i) —SO₂NHCONHR⁹,    -   (j) —SO₂NHCO₂R¹⁰, or

R¹⁶ is

-   -   (a) H,    -   (b) C₁₋₆-alkyl, or    -   (c) benzyl, optionally substituted on the phenyl ring with 1-2        substituents selected from the group consisting of halo,        C₁₋₄-alkyl, C₁₋₄-alkoxy or —NO₂;

R²⁸ is

-   -   (a) aryl, or    -   (b) heteroaryl;

R²⁹ is

-   -   (a) —CHO,    -   (b) —CONH₂,    -   (c) —NHCHO,    -   (d) —CO—(C₁₋₆ perfluoralkyl),    -   (e) —S(O)_(r)—(C₁₋₆ perfluoroalkyl),

E is

-   -   (a) -(T)_(y)-(B)_(y)—X²—(B)_(y)—R²⁸,    -   (b) -T-(B)_(y)—R²⁸,    -   (c) -(T)_(y)-(B)_(y)—X²—B or,    -   (d) -T-(B)_(y)—R²⁹;

L¹ is

-   -   (a) —CO₂—,    -   (b) —CONR^(11a)—,    -   (c) —NR^(11a)CO₂—,    -   (d) —NR^(11a)CONR^(11b)—;

B is C₁-C₆ alkyl;

-   -   X² is    -   (a) —CO—,    -   (b) —O—,    -   (c) —S(O)_(r)—,    -   (d) —(C₁-C₄-alkylene)-,    -   (e) —R^(11a)CONR^(11b)—,    -   (f) —CONR^(11a)—,    -   (g) —NR^(11a)CO—,    -   (h) —SO₂NR¹⁶—,    -   (i) —NR¹⁶SO₂—,    -   (j) —CONR^(11a)SO₂—,    -   (k) —SO₂NR^(11a)CO—,    -   (l) —SO₂NR^(11a)CO₂—,    -   (m) —OCONR^(11a)SO₂—,    -   (n) —SO₂NR^(11a)CONR^(11b)—,    -   (o) —NR^(11a)CONR^(11b)SO₂—,    -   (p) —SO₂NR^(11a)SO₂—,    -   (q) —CONR^(11a)SO₂NR^(11b)—, or    -   (r) —NR^(11a)SO₂NR^(11b)CO—

and pharmaceutically compatible salts of these compounds.

Another illustrative example of the specific embodiments described aboveis a compound of formula (VIb)

wherein:

R² is independently

-   -   (a) H,    -   (b) halo (F, Cl, Br, I), or    -   (c) C₁₋₄-alkyl;

R³ is

-   -   (a) H, or    -   (b) halo (F, Cl, Br, I);

R⁶ is

-   -   (a) C₁₋₁₀ alkyl,    -   (b) C₃₋₁₀ alkenyl, or    -   (c) C₃₋₁₀ alkynyl;

R⁹ is

-   -   (a) H,    -   (b) C₁₋₅-alkyl,    -   (c) aryl    -   (d) —(C₁₋₄-alkyl)-aryl, or    -   (e) heteroaryl;

R¹⁰ is

-   -   (a) aryl,    -   (b) C₃₋₇-cycloalkyl,    -   (c) C₁₋₄-perfluoroalkyl,    -   (d) C₁₋₄-alkyl, optionally substituted with a substituent        selected from the group consisting of aryl, heteroaryl, —OH,        —SH, C₁₋₄-alkyl, C₁₋₄-alkoxy, C₁₋₄-alkylthio, —CF₃, halo, —NO₂,        —CO₂R¹², —NH₂, —C₁₋₄-alkylamino, C₁₋₄-dialkylamino, —PO₃H₂, or    -   (e) heteroaryl;

R¹¹, R^(11a) and R^(11b) are independently

-   -   (a) H,    -   (b) C₁₋₆-alkyl,    -   (c) C₃₋₆-cycloalkyl,    -   (d) aryl,    -   (e) —(C₁₋₅-alkyl)-aryl, or    -   (f) heteroaryl;

R¹³ is

-   -   (a) —CO₂H,    -   (b) —CONHSO₂R¹⁰,    -   (c) —CONHSO₂NHR⁹,    -   (d) —NHCONHSO₂R¹⁰,    -   (e) —NHSO₂R¹⁰,    -   (f) —NHSO₂NHCOR¹⁰,    -   (g) —SO₂NHR⁹,    -   (h) —SO₂NHCOR¹⁰,    -   (i) —SO₂NHCONHR⁹,    -   (j) —SO₂NHCO₂R¹⁰, or

R¹⁶ is

-   -   (a) H,    -   (b) C₁₋₆-alkyl, or    -   (c) benzyl, optionally substituted on the phenyl ring with 1-2        substituents selected from the group consisting of halo,        C₁₋₄-alkyl, C₁₋₄-alkoxy or NO₂;

R²⁸ is

-   -   (a) aryl, or    -   (b) heteroaryl;

R²⁹ is

-   -   (a) —CHO,    -   (b) —CONH₂,    -   (c) —HCHO,    -   (d) —CO—(C₁-C₆ perfluoroalkyl),    -   (e) —S(O)_(r)—(C₁-C₆ perfluoroalkyl),

G is

-   -   (a) -(T)_(y)-(B)_(y)—X²—(B)_(y)—R²⁸,    -   (b) -T-(B)_(y)—R²⁸,    -   (c) -(T)_(y)-(B)_(y)—X²—B, or    -   (d) -T-(B)_(y)—R²⁹;

L² is —CO—, —NR^(11a)CO— or —O₂C—;

B is C₁₋₆ alkyl;

X₂ is

-   -   (a) —CO—,    -   (b) —O—,    -   (c) —S(O)_(r)—,    -   (d) —(C₂₋₄-alkylene)-,    -   (e) —NR^(11a) CO, —NR^(11a)CONR^(11b)—    -   (f) —CONR^(11a)—,    -   (g) —NR^(11a)CO—,    -   (h) —SO₂NR¹⁶—,    -   (i) —NR¹⁶SO₂—,    -   (j) —O₂NR^(11a) SO₂—,    -   (k) —SO₂NR^(11a)CO₂—,    -   (l) —SO₂NR^(11a)CO₂—,    -   (m) —OCONR^(11a)SO₂—,    -   (n) —SO₂NR^(11a)CONR^(11b)—,    -   (o) —N^(R11a)CONR^(11b)SO₂—,    -   (p) —SO₂NR^(11a)SO₂—,    -   (q) —CONR^(11a)SO₂NR^(11b)—, or    -   (r) —NR^(11a)SO₂NR^(11b)CO—,

and pharmaceutically compatible salts of these compounds.

Illustrative of the compounds according to the specific embodimentsmentioned above are the following:

-   1-[[2′-[[(isopentoxycarbonyl)amino]sulfonyl]-3-fluoro(1,1′-biphenyl)-4-yl]methyl]-5-13-(N-pyridin-3    ylbutanamido)propanoyl]-4-ethyl-2-propyl-1H-imidazole (XR510);-   1-((2′-((i-Amyloxycarbonylamino)sulfonyl)-3-fluoro-(1,1′-biphenyl)-4-yl)methyl)-5-[2-(N-benzoyl-N-phenylamino)ethylcarbonyl]-4-ethyl-2-propyl-1H-imidazole;-   1-((2′-((n-Butyloxycarbonylamino)sulfonyl)-3-fluoro-(1,1′-biphenyl)-4-yl)methyl)-5-[2-(N-benzoyl-N-phenylamino)ethylcarbonyl]-4-ethyl-2-propyl-1H-imidazole;-   1-((2′-((n-Propyloxycarbonylamino)sulfonyl)-3-fluoro-(1,1′-biphenyl)-4-yl)methyl)-5-[2-(N-benzoyl-N-phenylamino)ethylcarbonyl]-4-ethyl-2-propyl-1H-imidazole;-   1-((2′-((n-Butyloxycarbonylamino)sulfonyl)-3-fluoro-(1,1′-biphenyl)-4-yl)methyl)-5-[2-(N-benzoyl-N-butylamino)ethylcarbonyl]-4-ethyl-2-propyl-1H-imidazole;-   1-((2′-((n-Butyloxycarbonylamino)sulfonyl)-3-fluoro-(1,1′-biphenyl)-4-yl)methyl)-5-[2-(N-benzoyl-N-propylamino)ethylcarbonyl]-4-ethyl-2-prop    yl-1H-imidazole;-   1-((2′-((n-Butyloxycarbonylamino)sulfonyl)-3-fluoro-(1,1′-biphenyl)-4-yl)methyl)-5-[2-(N-butyryl-N-propylamino)ethylcarbonyl]-4-ethyl-2-propyl-1H-imidazole;-   1-((2′-((n-Butyloxycarbonylamino)sulfonyl)-3-fluoro-(1,1′-biphenyl)-4-yl)methyl)-5-[2-(N-butyryl-N-phenylamino)ethylcarbonyl]-4-ethyl-2-propyl-1H-imidazole;-   1-((2′-((i-Amyloxycarbonylamino)sulfonyl)-3-fluoro-(1,1′-biphenyl)-4-yl)methyl)-5-[2-(N-butyryl-N-phenylamino)ethylcarbonyl]-4-ethyl-2-propyl-1H-imidazole;-   1-((2′-((i-Amyloxycarbonylamino)sulfonyl)-3-fluoro-(1,1′-biphenyl)-4-yl)methyl)-5-[2-(N-isonicotinoyl-N-pyridin-3-ylamino)ethylcarbonyl]-4-ethyl-2-propyl-1H-imidazole;-   1-((2′-((n-Butyloxycarbonylamino)sulfonyl)-3-fluoro-(1,1′-biphenyl)-4-yl)methyl)-5-[2-(N-isonicotinoyl-N-pyridin-3-ylamino)ethylcarbonyl]-4-ethyl-2-propyl-1H-imidazole;-   1-((2′-((n-Butyloxycarbonylamino)sulfonyl)-3-fluoro-(1,1′-biphenyl)-4-yl)methyl)-5-[2-(N-nicotinoyl-N-pyridin-3-ylamino)ethylcarbonyl]-4-ethyl-2-propyl-1H-imidazole;-   1-((2′-((i-Amyloxycarbonylamino)sulfonyl)-3-fluoro-(1,1′-biphenyl)-4-yl)methyl)-5-[2-(N-nicotinoyl-N-pyridin-3-ylamino)ethylcarbonyl]-4-ethyl-2-propyl-1H-imidazole;-   1-((2′-((i-Amyloxycarbonylamino)sulfonyl)-3-fluoro-(1,1′-biphenyl)-4-yl)methyl)-5-[2-(N-nicotinoyl-N-pyridin-2-ylamino)ethylcarbonyl]-4-ethyl-2-propyl-1H-imidazole;-   1-((2′-((i-Amyloxycarbonylamino)sulfonyl)-3-fluoro-(1,1′-biphenyl)-4-yl)methyl)-5-[2-(N-isonicotinoyl-N-phenylamino)ethylcarbonyl]-4-ethyl-2-propyl-1H    imidazole;-   1-((2′-((i-Amyloxycarbonylamino)sulfonyl)-3-fluoro-(1,1′-biphenyl)-4-yl)methyl)-5-[2-(N-butyryl-N-pyridin-3-ylamino)ethylcarbonyl]-4-ethyl-2-propyl-1H    imidazole;-   1-((2′-((i-Amyloxycarbonylamino)sulfonyl)-3-fluoro-(1,    r-biphenyl)-4-yl)methyl)-5-[2-(N-isobutyryl-N-pyridin-3-ylamino)ethylcarbonyl]-4-ethyl-2-propyl-1H-imidazole;-   1-((2′-((n-Butyloxycarbonylamino)sulfonyl)-3-fluoro-(1,1′-biphenyl)-4-yl)methyl)-5-[2-(N-acetyl-N-pyridin-3-ylamino)ethylcarbonyl]-4-ethyl-2-propyl-1H-imidazole;-   1-((2′-((i-Amyloxycarbonylamino)sulfonyl)-3-fluoro-(1,1′-biphenyl)-4-yl)methyl)-5-[2-(N-butyryl-N-pyridin-2-ylamino)ethylcarbonyl]-4-ethyl-2-propyl-1H-imidazole-   1-((2′-((i-Amyloxycarbonylamino)sulfonyl)-(1,1′-biphenyl)-4-yl)methyl)-5-[2-(N-butyryl-N-pyridin-3-ylamino)ethylcarbonyl]-2-butyl-4-chloro-1H-imidazole;-   1-((2′-((i-amyloxycarbonylamino)sulfonyl)-3-fluoro-(1,1′-biphenyl)-4-yl)methyl)-5-[2-(N-propionyl-N-pyridin-3-ylamino)ethylcarbonyl]-4-ethyl-2-propyl-1H-imidazole;-   1-((2′-((i-Amyloxycarbonylamino)sulfonyl)(1,1′-biphenyl)-4-yl)methyl)-5-[2-(N-nicotinoyl-N-pyridin-3-ylamino)ethylcarbonyl]-4-ethyl-2-propyl-1H-imidazole;-   1-((2′-((i-Amyloxycarbonylamino)sulfonyl)(1,1′-biphenyl)-4-yl)methyl)-5-[2(N-butyryl-N-pyridin-3-ylamino)ethylcarbonyl]-4-ethyl-2-propyl-1H-imidazole;-   1-((2′-((n-Butyloxycarbonyl-amino)sulfonyl)-3-fluoro-(1,1′-biphenyl)-4-yl)methyl)-4-ethyl-5-(2-(2-phenoxyphenyl)ethylcarbonyl)-2-propyl-1H-imidazole;-   4-[((5-(2-Benzoylbenzyloxycarbonyl)-4-ethyl-2-n-propyl)imidazol-1-yl)methyl]-3-fluoro-2′-n-butyloxycarbonylaminosulfonyl-1,1′-biphenyl;-   4-[((5-(2-Benzoylbenzyloxycarbonyl)-4-ethyl-2-n-propyl)imidazol-1-yl)methyl]-3-fluoro-2′-((2-phenyl)ethyloxycarbonylaminosulfonyl)-1,1′-biphenyl;-   4-[((5-(2-Benzoylbenzyloxycarbonyl)-4-ethyl-2-n-propyl)imidazol-1-yl)methyl]-2′-((2-phenyl)ethyloxycarbonylaminosulfonyl)-1,1′-biphenyl;-   4-[((5-(2-Benzoylbenzyloxycarbonyl)-4-ethyl-2-n-propyl)imidazol-1-yl)methyl]-3-fluoro-2′-n-butyloxycarbonylaminosulfonyl-1,1′-biphenyl;-   4-[((5-(2-Benzoylbenzyloxycarbonyl)-4-ethyl-2-n-propyl)imidazol-1-yl)methyl]-3-fluoro-2′-n-isoamyloxycarbonylaminosulfonyl-1,1′-biphenyl;-   4-[((5-(2-Benzoylbenzyloxycarbonyl)-4-ethyl-2-n-propyl)imidazol-1-yl)methyl]-2′-n-isoamyloxycarbonylaminosulfonyl-1,1′-biphenyl;-   4-[((5-(2-Benzoylbenzyloxycarbonyl)-4-ethyl-2-n-propyl)imidazol-1-yl)methyl]-3-fluoro-2′-n-propyloxycarbonylaminosulfonyl-1,1′-biphenyl;-   4-[((5-(2-Isoamyloxybenzyloxycarbonyl)-4-ethyl-2-n-propyl)imidazol-1-yl)methyl]-3-fluoro-2′-n-butyloxycarbonylaminosulfonyl-1,1′-biphenyl;-   4-[((5-(2-Phenylaminocarbonyl)benzyloxycarbonyl-4-ethyl-2-n-propyl)imidazol-1-yl)methyl]-3-fluoro-2′-n-butyloxycarbonylaminosulfonyl-1,1′-biphenyl;-   4-[((5-(2-Benzoylbenzyloxycarbonyl)-4-ethyl-2-n-propyl)imidazol-1-yl)methyl]-3-fluoro-2′-(1H-tetrazol-5-yl)-1,1′-biphenyl;-   4-[((5-)2-trifluorophenyl)methylaminocarbonyl)-4-ethyl-2-n-propyl)imidazol-1-yl)methyl]-3-fluoro-2′-isoamyloxycarbonylaminosulfonyl-1,1′-biphenyl;-   N-butyl,N-benzyl-2-(aminocarbonyl)ethynylmethyl    4-ethyl-2-propyl-1-[[2′-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]imidazole-5-carboxylate;-   N,N-diphenyl-2-(aminocarbonyl)ethynylmethyl    4-ethyl-2-propyl-1-[[2′-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]imidazole-5-carboxylate;-   N-phenyl-2-(aminocarbonyl)ethyl4-ethyl-2-propyl-1-[[2′-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]imidazole-5-carboxylate,-   N-butyl,N-benzyl-4-(aminocarbonyl)propyl4-ethyl-2-propyl-1-[[2′-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]imidazole-5-carboxylate;-   N,N-dipentyl-4-(aminocarbonyl)propyl    4-ethyl-2-propyl-1-[[2′-(tetrazol-5-yl)biphenyl-4-yl]methyl]imidazole-5-carboxylate;-   4-[(5-((2-benzoyl)phenylcarbonyloxymethyl)-4-chloro-2-n-propylimidazol-1-yl)methyl]-3-fluoro-2′-isoamyloxycarbonylaminosulfonylbiphenyl;    and-   1-((2′-((n-butyloxycarbonylamino)sulfonyl)-3-fluoro-(1,1′-biphenyl)-4-yl)methyl)-2-(n-propyl)-4-ethyl-5-(2-(phenoxy)phenoxy)acetyl-1H-imidazole.

In the embodiments described above for compounds according to formulae(VI)-(VIb), when an alkyl substituent is mentioned, the normal alkylstructure is meant (e.g. butyl is n-butyl) unless otherwise specified.However, in the definition of radicals above (e.g. R³), both branchedand straight chains are included in the scope of alkyl, alkenyl andalkynyl.

In the embodiments described above for compounds according to formulae(VI)-(VIb), the term “aryl” is meant to include phenyl, biphenyl,napthyl, or fluorenyl group optionally substituted with one to threesubstituents selected from the group consisting of —OH, —SH,C₁-C₄-alkyl, C₁-C₄-alkoxy, —CF₃, halo, —NO₂, —CO₂H, —CO₂CH₃,—CO₂-benzyl, —NH₂, —NH(C₁-C₄-alkyl), —N(C₁-C₄-alkyl)₂. The termheteroaryl is meant to include unsubstituted, monosubstituted ordisubstituted 5- to 10-membered mono- or bicyclic aromatic rings whichcan optionally contain from 1 to 3 heteroatoms selected from the groupconsisting of O, N, and S. Included in the definition of the groupheteroaryl, but not limited to, are the following: pyridyl, pyridazinyl,pyrimidinyl, pyrazinyl, 1,3,5-triazinyl, furyl, thiophenyl, imidazolyl,oxazolyl, thiazolyl, benzofuranyl, benzothiophenyl, benzimidazolyl,benzoxazolyl, benzothiazolyl, indolin-2-onyl, indolinyl, indolyl,pyrrolyl, quinonlinyl and isoquinolinyl. Particularly preferred are 2-,3-, or 4-pyridyl; 2-, or 3-furyl; 2-, or 3-thiophenyl; 2-, 3-, or4-quinolinyl; or 1-, 3-, or 4-isoquinolinyl optionally substituted withone to three substituents selected from the group consisting of —OH,—SH, C₁-C₄-alkyl, C₁-C₄-alkoxy, —CF₃, halo, —NO₂, —CO₂H, —CO₂CH₃,—CO₂-benzyl, —NH₂, —NH(C₁-C₄-alkyl), —N(C₁-C₄-alkyl)₂. The term aryleneis meant to include a phenyl, biphenyl, napthyl, or fluorenyl groupwhich is used as a link for two groups to form a chain. Included in thedefinition of arylene, but not limited to, are the following isomericlinkers: 1,2-phenyl, 1,3-phenyl, 1,4-phenyl; 4,4′-biphenyl,4,3′-biphenyl, 4,2′-biphenyl, 2,4′-biphenyl, 2,3′-biphenyl,2,2′-biphenyl, 3,4′-biphenyl, 3,3′-biphenyl, 3,2′-biphenyl; 1,2-napthyl,1,3-napthyl, 1,4-napthyl, 1,5-napthyl, 1,6-napthyl, 1,7-napthyl,1,8-napthyl, 2,6-napthyl, 2,3-napthyl; 1,4-fluorenyl. Particularlypreferred are 1,2-phenyl, 1,3-phenyl, 1,4-phenyl, 4,4′-biphenyl,3,3′-biphenyl, and 2,2′-biphenyl optionally substituted with one tothree substituents selected from the group consisting of —OH, —SH,C₁-C₄-alkyl, alkoxy, —CF₃, halo, —NO₂, —CO₂H, —CO₂CH₃, —CO₂-benzyl,—NH₂, —NH(C₁-C₄-alkyl), alkyl)₂.

In the embodiments described above for compounds according to formulae(VI)-(VIb), the term heteroarylene is meant to include unsubstituted 5-to 10-membered aromatic ring which can optionally contain from 1 to 3heteroatoms selected from the group consisting of O, N, and S which isused as a link for two groups to form a chain. Included in thedefinition of the group heteroaryl, but not limited to, are thefollowing: 2,3-pyridyl, 2,4-pyridyl, 2,5-pyridyl, 2,6-pyridyl,3,4-pyridyl, 3,5-pyridyl, 3,6-pyridyl; 2,3-furyl, 2,4-furyl, 2,5-furyl;2,3-thiophenyl, 2,4-thiophenyl, 2,5-thiophenyl; 4,5-imidazolyl,4,5-oxazolyl; 4,5-thiazolyl; 2,3-benzofuranyl; 2,3-benzothiophenyl;2,3-benzimidazolyl; 2,3-benzoxazolyl; 2,3-benzothiazolyl;3,4-indolin-2-onyl; 2,4-indolinyl; 2,4-indolyl; 2,4-pyrrolyl;2,4-quinolinyl, 2,5-quinolinyl, 4,6-quinolinyl; 3,4-isoquinolinyl,1,5-isoquinolinyl. Particularly preferred are 2,3-pyridyl, 3,4-pyridyl,2,3-furyl, 3,4-furyl 2,3-thiophenyl, 3,4-thiophenyl, 2,3-quinolinyl,3,4-quinolinyl and 1,4-isoquinolinyl optionally substituted with one tothree substituents selected from the group consisting of —OH, —SH,C₁-C₄-alkyl, C₁-C₄-alkoxy, —CF₃, halo, —NO₂, —CO₂H, —CO₂CH₃,—CO₂-benzyl, —NH₂, —NH(C₁-C₄-alkyl), —N(C₁-C₄-alkyl)₂;

It should be noted in the foregoing structural formula, when a radicalcan be a substituent in more than one previously defined radical, thatfirst radical (R^(#), B or y) can be selected independently in eachpreviously defined radical. For example, R¹ and R² can each be—CONHOR¹². R¹² need not be the same substituent in each of R¹ and R²,but can be selected independently for each of them. Or if, for example,the same R group (let us take R², for instance) appears twice in amolecule, each of those R groups is independent of each other (one R²group may be —CONHOR¹², while the other R² group may be —CN).

In still other embodiments, the AT₂ receptor antagonist is selected fromthe compounds listed in U.S. Pat. No. 5,338,740 and especially in thecompound claims of this patent, which a heterocyclic ring (hereafterreferred to as “Het”) is connected to an aryl or thienyl group(hereafter referred to as “Ar”) via a carbobicyclic or heterobicyclicspacer group (hereafter referred to as “W”). Representative examples ofsuch compounds are represented by the formula (VII):

Ar-W-Het  (VII)

-   -   wherein:    -   Ar is selected from the group consisting of

-   -   and X¹, X², X³ and X⁴ are independently selected from CR² and        nitrogen;    -   one of X⁵ and X⁶ is CH and the other is S;    -   R¹ is selected from the group consisting of CO₂H, —NHSO₂CF₃,        —CONHSO₂—(C₁-C₈)alkyl, PO₃H₂, SO₃H, —CONHSO₂(C₆H₅), —CONHSO₂CF₃,        tetrazole,

-   -   and —SO₂NHCO₂—(C₁-C₈)alkyl;    -   R² is selected from hydrogen, (C₁-C₈)alkyl, (C₂-C₁₀)alkenyl,        (C₃-C₈)cycloalkyl, halo, hydroxy, —O—(C₁-C₆)alkyl,        —S—(C₁-C₆)alkyl, —SO—(C₁-C₆)alkyl —SO₂—(C₁-C₆)alkyl, —NR³R⁴, and        phenyl, wherein said phenyl is optionally mono-, di- or        tri-substituted with substituents independently selected from        hydrogen, (C₁-C₈)alkyl, (C₂-C₁₀)alkenyl, (C₃-C₈)cycloalkyl,        halo, (C₁-C₆)alkoxy, —S—(C₁-C₆)alkyl, —SO—(C₁-C₆)alkyl,        —SO₂—(C₁-C₆)alkyl, —O—(C₁-C₆)alkyl, and —NR³R⁴;    -   R³ and R⁴ are independently selected from hydrogen,        (C₁-C₈)alkyl, (C₂-C₁₀)alkenyl and (C₃-C₈)cycloalkyl, or R³ and        R⁴, together with the nitrogen to which they are attached, form        a cyclic 5-7 membered saturated or partially saturated        carbocyclic or heterocyclic ring with one or two heteroatoms        independently selected from nitrogen, oxygen and sulfur; and the        dotted line represents that the ring containing X⁵ and X⁶ is        aromatic:

W is a carbobicyclic or heterobicyclic ring system having the formula:

-   -   and X⁸, X⁹, X¹⁰ and X¹¹ are present or absent, and each of X⁷,        X⁸, X⁹, X¹⁰ and X¹¹ is independently selected from CHR⁵, O, S,        SO, SO², and NR⁶;    -   X¹², X¹³, and X¹⁴ are independently selected from CR⁷ or N;    -   X¹⁵ and X¹⁶ are independently selected from CR⁷ and S;    -   R⁵ is absent when the CH moiety of CHR⁵ is connected to Het and        when R⁵ is present it is selected from hydrogen, (C₁-C₈)alkyl,        (C₂-C₁₀)alkenyl, (C₃-C₈)cycloalkyl, —O—(C₁-C₆)alkyl, and phenyl,        wherein said phenyl is optionally mono-, di- or tri-substituted        with substituents independently selected from hydrogen,        (C₁-C₈)alkyl, (C₂-C₁₀)alkenyl, (C₃-C₈)cycloalkyl, halo,        (C₁-C₆)alkoxy, —S—(C₁-C₆)alkyl, —SO—(C₁-C₆)alkyl,        —SO₂—(C₁-C₆)alkyl, —O—(C₁-C₆)alkyl, and —NR³R⁴;    -   R⁶ is selected from (C₁-C₈)alkyl, (C₃-C₈)cycloalkyl and phenyl,        wherein said cycloalkyl is saturated or partially saturated and        wherein said cycloalkyl may optionally contain a heteroatom        selected from nitrogen, oxygen, and sulfur, and said phenyl is        optionally mono-, di- or tri-substituted with substituents        independently selected from hydrogen, (C₁-C₈)alkyl,        (C₁-C₁₀)alkenyl, (C₃-C₈)cycloalkyl, halo, (C₁-C₆)alkoxy,        —S—(C₁-C₆)alkyl, —SO—(C₁-C₆)alkyl, —SO₂—(C₁-C₆)alkyl,        —O—(C₁-C₆)alkyl, and —NR³R⁴;    -   R⁷ is selected from hydrogen, (C₁-C₈)alkyl, (C₂-C₁₀)alkenyl,        (C₃-C₈)cycloalkyl, halo, hydroxy, —O—(C₁-C₆)alkyl,        —S—(C₁-C₆)alkyl, —SO—(C₁-C₆)alkyl, —SO₂—(C₁-C₆)alkyl, —NR³R⁴,        and phenyl, wherein said phenyl is optionally mono-, di- or        tri-substituted with substituents selected from hydrogen,        (C₁-C₈)alkyl, (C₁-C₁₀)alkenyl, (C₃-C₈)cycloalkyl, halo,        (C₁-C₆)alkoxy, —S—(C₁-C₆)alkyl, —SO—(C₁-C₆)alkyl,        —SO₂—(C₁-C₆)alkyl, —O—(C₁-C₆)alkyl, and —NR³R⁴;    -   and the dotted line represents that the ring containing X¹⁵ and        X¹⁶ contain one or two double bonds; and    -   Het is selected from the group consisting of:

-   -   and R⁸, R⁹, R¹⁰ and R¹¹ are independently selected from        hydrogen, (C₁-C₈)alkyl, (C₁-C₁₀)alkenyl, (C₃-C₈)cycloalkyl,        halo, (C₁-C₅)alkoxy, —SO—(C₁-C₆)alkyl, —CO₂H, —SO₂NR₃R₄, —NR₃R₄,        and phenyl, wherein said phenyl is optionally mono-, di-, or        tri-substituted with halo, hydroxy, nitro, (C₁-C₈)alkyl,        (C₃-C₆)cycloalkyl, (C₁-C₇)alkoxy, (C₁-C₇)alkylthio, and amino,        wherein said amino is optionally mono- or disubstituted with        (C₁-C₇)alkyl;    -   and wherein each occurrence of R³ can be the same or different        from any other occurrence of R³, and each occurrence of R⁴ can        be the same or different from any other occurrence of R⁴;    -   with the proviso that: (a) no more than two of X¹, X², X³ and X⁴        can be nitrogen; and (b) at least two of X⁷, X⁸, X⁹, X¹⁰ and X¹¹        are present;

and to pharmaceutically compatible salts thereof.

As used herein for compounds according to formula (VII):

the term “halo,” unless otherwise indicated, includes chloro, fluoro,bromo and dodo;

the term “alkyl”, unless otherwise indicated, includes saturatedmonovalent hydrocarbon radicals having straight, branched or cyclicmoieties or combinations thereof, for example methyl, ethyl, n-propyl,isopropyl, n-butyl, isobutyl and t-butyl;

the term “alkenyl,” unless otherwise indicated, means straight orbranched unsaturated hydrocarbon radicals, for example, ethenyl, 1- or2-propenyl, 2-methyl-1-propenyl and 1- or 2-butenyl;

the term “cycloalkyl,” unless otherwise indicated, means a saturatedcarbocyclic radical, for example, cyclopropyl, cyclobutyl, cyclopentyland cyclohexyl; and

the term “alkoxy”, unless otherwise indicated, includes O-alkyl groupswherein “alkyl” is defined as above.

In specific embodiments, compounds according to formula (VII) includethose wherein W has the formula

Examples of specific preferred compounds according to formula (VII) are:

-   2-butyl-5-chloro-1-{5-[2-(1H-tetrazol-5-yl)-phenyl]-indan-1-yl}-1H-imidazole-4-carboxylic    acid ethyl ester;-   2-butyl-5-chloro-1-{5-[2-(1H-tetrazol-5-yl)-phenyl]-indan-1-yl}-1H-imidazole-4-carboxylic    acid;-   2-butyl-3-{5-[2-(1H-tetrazol-5-yl)-phenyl]-indan-1-yl}-1,3-diazaspiro[4.4]non-1-en-4-one;-   (2-butyl-5-chloro-1-{5-[2-(1H-tetrazol-5-yl)-phenyl]-indan-1-yl}-1H-imidazol-4-yl)methanol-   2-ethyl-5,7-dimethyl-3-{5-[2-(1H-tetrazol-5-yl)-phenyl}-indan-1-yl}-3H-imidazole[4,5-b]pyridine;-   (S)-2-ethyl-5,7-dimethyl-3-{5-[2-(1H-tetrazol-5-yl)-phenyl]-indan-1-yl}-3H-imidazo[4,5-b]pyridine;-   (R)-2-ethyl-5,7-dimethyl-3-{5-[2-(1H-tetrazol-5-yl)-phenyl]-indan-1-yl}-3H-imidazol[4,5-b]pyridine;-   2-ethyl-7-methyl-3-{5-[2-(1H-tetrazol-5-yl)-phenyl}-indan-1-yl)-3H-imidazo[4,5-b]pyridine;-   5,7-dimethyl-2-propyl-3-{5-[2-(1H-tetrazol-5-yl)-phenyl]-indan-1yl}-3H-imidazo[4,5-b]pyridine;-   2-cyclopropyl-5,7-dimethyl-3-{5-[2-(1H-tetrazol-5-yl)-phenyl]-indan-1-yl}-3H-imidazo[4,5-b]pyridine;-   2-butyl-5,7-dimethyl-3-{5-[2-(1H-tetrazol-5-yl)-phenyl]-indan-1-yl}-3H-imidazo[4,5-b]pyridine;-   2-butyl-3-{5-[2-(1H-tetrazol-5-yl)-phenyl]-indan-1-yl}-3H-imidazo[4,5-b]pyridine;-   2-[1-(2-ethyl-5,7-dimethyl-imidazo[4,5-b]pyridin-3-yl)-indan-5-yl-benzoic    acid;-   2-[5-(2-ethyl-5,7-dimethyl-imidazo[4,5-b]pyridin-3-yl)-5,6,7,8-tetrahydro-4H-naphthalen-2-yl]-benzoic    acid;-   2-ethyl-5,7-dimethyl-3-{6-[2-(1H-tetrazol-5-yl)-phenyl]-1,2,3,4-tetrahydro-4H-naphthalen-1-yl}-3H-imidazo[4,5-b]pyridine;-   2-ethyl-5,7-dimethyl-3-{2-[2-(1H-tetrazol-5-yl)-phenyl]-6,7,8,9-tetrahydro-5H-benzocyclohepten-5-yl}-3H-imidazo[4,5-b]pyridine;-   2-ethyl-5,7-dimethyl-3-{7-[2-(1H-tetrazol-5-yl)-phenyl]-chroman-4-yl}-3H-imidazo[4,5-b]pyridine;-   2-ethyl-5,7-dimethyl-3-{3-[2-(1H-tetrazol-5-yl)-phenyl]-bicyclo[4.2.0]octa-1,3,5-trien-7-yl}-3H-imidazo[4,5-b]pyridine;-   2-ethyl-5,7-dimethyl-3-{7-[2-(1H-tetrazol-5-yl)-phenyl]-chroman-4-yl}-3H-imidazo[4,5-b]pyridine;-   2-ethyl-5,7-dimethyl-3-{3-[2-(1H-tetrazol-5-yl)-phenyl]-6,7-dihydro-5H-[1]pyridin-7-yl}-3H-imidazo[4,5-b]pyridine;-   2-[5-(2-butyl-imidazo[4,5-b]pyridin-3-yl)-naphthalen-2-yl]-benzoic    acid;-   2-butyl-3-{6-[2-(1H-tetrazol-5-yl)-phenyl]-naphthalen-1-yl}3H-imidazo[4,5-b]pyridine;    and-   2-ethyl-5,7-dimethyl-3-{6-[2-(1H-tetrazol-5-yl)-phenyl-naphthalen-1-yl}-3H-imidazo[4,5-b]pyridine.

Other compounds of according to formula (VII) include the following:

-   2-ethyl-5,7-dimethyl-3-{7-[2-(2H-tetrazol-5-yl)-phenyl]-thiochroman-4-yl}-3H-imidazo[4,5-b]pyridine;-   3-{1,1-dioxo-7-[2-(2H-tetrazol-5-yl)-phenyl]-thiochroman-4-yl}-2-ethyl-5,7-dimethyl-3H-imidazo[4,5-b]pyridine;-   2-ethyl-5,7-dimethyl-3-{2-[2-(2H-tetrazol-5-yl)-phenyl]-5,6-dihydro-4H-thieno[2,3-b]thiopyran-4-yl}-3H-imidazo[4,5-b]pyridine;-   2-ethyl-5,7-dimethyl-3-{2-[2-(2H-tetrazol-5-yl)-phenyl]-4,5,6,7-tetrahydrobenzo[b]thiophen-4-yl}-3H-imidazo[4,5-b]pyridine;    P0    2-ethyl-5,7-dimethyl-3-{2-[2-(2H-tetrazol-5-yl)-phenyl]-5,6-dihydro-4H-cyclopenta[b]thiophen-4-yl}-3H-imidazo[4,5-b]pyridine;-   2-ethyl-5,7-dimethyl-3-{6-[2-(2H-tetrazol-5-yl)-phenyl]-3,4-dihydro-2H-thieno[2,3-b]pyran-4-yl}-3H-imidazo[4,5-b]pyridine;-   2-ethyl-5,7-dimethyl-3-{2-[2-(2H-tetrazol-5-yl)-phenyl]-6,7-dihydro-5H-[1]pyridin-5-yl}-3H-imidazo[4,5-b]pyridine;-   5-(2-ethyl-5,7-dimethyl-imidazo[4,5-b]pyridin-3-yl)-2-[2-(2H-tetrazol-5-yl)-phenyl]-5,6,7,8-tetrahydro-quinoline;-   4-(2ethyl-5,7-dimethyl-imidazo[4,5-b]pyridin-3-yl)-7-[2-(2H-tetrazol-5-yl)-phenyl]-3,4-dihydro-2H-thiopyrano[2,3-b]pyridine-1,1-dioxide;-   2-ethyl-5,7-dimethyl-3-{2-[2-(2H-tetrazol-5-yl)-phenyl]-6,7-dihydro-5H-cyclopentapyrimidin-5-yl}-3H-imidazo[4,5-b]pyridine;-   2-ethyl-5,7-dimethyl-3-{3-[2-(2H-tetrazol-5-yl)-phenyl]-6,7-dihydro-5H-[2]pyrindin-7-yl}-3H-imidazo[4,5-b]pyridine;-   2-ethyl-5,7-dimethyl-3-{5-[3-(2H-tetrazol-5-yl)-thiophen-2-yl]-indan-1-yl}-3H-imidazo[4,5-b]pyridine;-   2-ethyl-5,7-dimethyl-3-{5-[2-(2H-tetrazol-5-yl)-thiophen-3-yl]-indan-1-yl}-3H-imidazo[4,5-b]pyridine;-   2-ethyl-5,7-dimethyl-3-{5-[4-(2H-tetrazol-5-yl)-thiophen-3-yl]-indan-1-yl}-3H-imidazo[4,5-b]pyridine;-   2-ethyl-5,7-dimethyl-3-{5-[3-(2H-tetrazol-5-yl)-pyridin-4-yl]-indan-1-yl}-3H-imidazo[4,5-b]pyridine;-   2-ethyl-5,7-dimethyl-3-{5-[4-(2H-tetrazol-5-yl)-pyridin-3-yl]-indan-1-yl}-3H-imidazo[4,5-b]pyridine;-   2-ethyl-5,7-dimethyl-3-{5-[3-(2H-tetrazol-5-yl)-pyridin-2-yl]-indan-1-yl}-3H-imidazo[4,5-b]pyridine;-   (2-butyl-5-chloro-3-{5-[2-(2H-tetrazol-5-yl)-phenyl]-indan-1-yl}-3H-imidazole-4yl)methanol;-   2-butyl-5-chloro-3-{5-[2-(2H-tetrazol-5-yl)-phenyl]-indan-1-yl}-3H-imidazole-4-carboxylic    acid;-   2-butyl-5-(1,1,2,2,2-pentafluoro-ethyl)-3-{5-[2-(2H-tetrazol-5-yl)-phenyl]-indan-1-yl}-3H-imidazole-4-carboxylic    acid;-   2-butyl-5-ethyl-3-{5-[2-(2H-tetrazol-5-yl)-phenyl]-indan-1-yl}-3H    -imidazole-4-carboxylic acid;-   2-ethoxy-3-{5-[2-(2H-tetrazol-5-yl)-phenyl]-indan-1-yl}-3H-benzoimidazole-4-carboxylic    acid;-   2-ethylsulfanyl-3-{5-[2-(2H-tetrazol-5-yl)-phenyl]-indan-1-yl}-3H-benzoimidazole-4-carboxylic    acid;-   N-benzoyl-2-[1-(2-ethyl-5,7-dimethyl-imidazo[4,5-b]pyridin-3-yl)-indan-5-yl]-benzenesulfonamide;    and-   N-{2-[1-(2-ethyl-5,7-dimethyl-imidazo[4,5-b]pyridin-3-yl)-indan-5-yl]-phenyl}-benzenesulfonamide.

Other illustrative AT₂ receptor antagonist compounds are described forexample by Rosentrö, Ulrika in a thesis entitled “Design and synthesisof AT₂ receptor antagonist selective angiotensin II analoguesencompassing β and γ turn mimetics”, 2004, Uppsala University, Sweden;and by Timmermans et al., 1993, Pharmacal Reviews 45(2): 205-251.

In further embodiments, the AT₂ receptor antagonist is selected from AT₂receptor antagonist peptides, illustrative examples of which includehexa-, hepta- and octapeptides represented by the formula:

(SEQ ID NO: 28) R₁-R₂-R₃-R₄-R₅-R₆-Pro-R₇ (VIII)

wherein:

-   -   R₁ is absent or is selected from hydrogen, succinyl, L-aspartyl,        sarcosyl, L-seryl, succinamyl, L-propyl, glycyl, L-tyrosyl,        N_(a)nicotinoyl-tyrosyl, or D- or L-asparagyl;    -   R₂ is selected from arginyl or N-benzoylcarbonyl arginyl;    -   R₃ is absent or valyl;    -   R₄ is absent or is selected from L-phenylalanyl or L-tyrosyl;    -   R₅ is selected from valyl, L-isoleucyl, L-alanyl or L-lysyl;    -   R₆ is selected from L-histidyl, L-isoleucyl, L-tyrosyl or        p-aminophenylalanyl; and    -   R₇ is selected from L-alanine, L-tyrosine, L- or D-leucine,        glycine, L-isoleucine or β-alanine residue.

and pharmaceutically acceptable salts of these peptides.

Representative examples according to formula (VIII) include, but are notlimited to:

H-Asn-Arg-Val-Tyr-Val-His-Pro-Ala-OH [SEQ ID NO: 1];

H-Asn-Arg-Val-Tyr-Val-His-Pro-Leu-OH [SEQ ID NO: 2];

Succinyl-Arg-Val-Tyr-Val-His-Pro-Ala-OH [SEQ ID NO: 3];

H-Asp-Arg-Val-Tyr-Val-His-Pro-Ala-OH [SEQ ID NO: 4];

H-Arg-Val-Tyr-Val-His-Pro-Ala-OH [SEQ ID NO: 5];

H-Sar-Arg-Val-Tyr-His-Pro-Ala-OH [SEQ ID NO: 6];

H-Ser-Arg-Val-Tyr-His-Pro-Ala-OH [SEQ ID NO: 7];

Succinamyl-Arg-Val-Tyr-Val-His-Pro-Ala-OH [SEQ ID NO: 8];

H-Asn-Arg-Val-Tyr-Val-His-Pro-Gly-OH [SEQ ID NO: 9];

H-Asn-Arg-Val-Tyr-Val-His-Pro-Ile-OH [SEQ ID NO: 10];

H-Sar-Arg-Val-Tyr-Val-His-Pro-Gly-OH [SEQ ID NO: 11];

H-Pro-Arg-Val-Tyr-Val-His-Pro-Gly-OH [SEQ ID NO: 12];

H-Asn-Arg-Val-Tyr-Val-His-Pro-Gly-OH [SEQ ID NO: 13];

H-Sar-Arg-Val-Tyr-Val-His-Pro-β-Ala-OH [SEQ ID NO: 14];

H-Asn-Arg-Val-Tyr-Val-His-Pro-β-Ala-OH [SEQ ID NO: 15];

H-Gly-Arg-Val-Tyr-Val-His-Pro-Ala-OH [SEQ ID NO: 16];

H-Sar-Arg-Val-Tyr-Ile-His-Pro-Leu-OH [SEQ ID NO: 17];

H-Asn-Arg-Val-Tyr-Val-His-Pro-Leu-OH [SEQ ID NO: 18];

H-Sar-Arg-Val-Tyr-Ile-His-Pro-Ala-OH [SEQ ID NO: 19], also known assaralasin;

H-Asn-Arg-Val-Tyr-Ile-His-Pro-Ala-OH [SEQ ID NO: 20];

H-Asn-Arg-Val-Tyr-Ala-His-Pro-Ala-OH [SEQ ID NO: 21];

H-Asp-Arg-Val-Phe-Ile-His-Pro-Tyr-OH [SEQ ID NO: 22], also known asPhe⁴-Tyr⁸-Ang II;

H-Asp-Arg-Val-Tyr-Ile-p-NH₂Phe-Pro-Phe-OH [SEQ ID NO: 23], also known as[p-NH₂Phe]⁶-Ang II; and

nicotinic acid-Tyr-(N-benzoylcarbonyl-Arg)-Lys-His-Pro-Ile-OH [SEQ IDNO: 24], also known as CGP-42112A;

In other embodiments, the AT₂ receptor antagonist is selected fromantigen-binding molecules that are immuno-interactive with an AT₂receptor polypeptide. Illustrative antigen-binding molecules includewhole polyclonal antibodies. Such antibodies may be prepared, forexample, by injecting an AT₂ receptor polypeptide or fragment thereofinto a production species, which may include mice or rabbits, to obtainpolyclonal antisera. Methods of producing polyclonal antibodies are wellknown to those skilled in the art. Exemplary protocols which may be usedare described for example in Coligan et al., “Current Protocols InImmunology”, (John Wiley & Sons, Inc, 1991), and Ausubel et al.,(Current Protocols in Molecular Biology”, John Wiley & Sons Inc,1994-1998), in particular Section III of Chapter 11.

In lieu of the polyclonal antisera obtained in the production species,monoclonal antibodies may be produced using the standard method asdescribed, for example, by Köhler and Milstein (1975, Nature 256,495-497), or by more recent modifications thereof as described, forexample, in Coligan et al., (1991, supra) by immortalizing spleen orother antibody-producing cells derived from a production species whichhas been inoculated with an AT₂ receptor polypeptide or fragmentthereof.

The invention also contemplates as antigen-binding molecules Fv, Fab,Fab′ and F(ab′)₂ immunoglobulin fragments. Alternatively, theantigen-binding molecule may be in the form of a synthetic stabilized Fvfragment, a single variable region domain (also known as a dAbs), a“minibody” and the like as known in the art.

Also contemplated as antigen binding molecules are humanized antibodies.Humanized antibodies are produced by transferring complementarydetermining regions from heavy and light variable chains of a non human(e.g., rodent, preferably mouse) immunoglobulin into a human variabledomain. Typical residues of human antibodies are then substituted in theframework regions of the non human counterparts. The use of antibodycomponents derived from humanized antibodies obviates potential problemsassociated with the immunogenicity of non human constant regions.General techniques for cloning non human, particularly murine,immunoglobulin variable domains are described, for example, by Orlandiet al. (1989, Proc. Natl. Acad. Sci. USA 86: 3833). Techniques forproducing humanized monoclonal antibodies are described, for example, byJones et al. (1986, Nature 321:522), Carter et al. (1992, Proc. Natl.Acad. Sci. USA 89: 4285), Sandhu (1992, Crit. Rev. Biotech. 12: 437),Singer et al. (1993, J. Immun. 150: 2844), Sudhir (ed., AntibodyEngineering Protocols, Humana Press, Inc. 1995), Kelley (“EngineeringTherapeutic Antibodies,” in Protein Engineering: Principles and PracticeCleland et al. (eds.), pages 399-434 (John Wiley & Sons, Inc. 1996), andby Queen et al., U.S. Pat. No. 5,693,762 (1997).

Illustrative antigen-binding molecules that are immuno-interactive withAT₂ receptor polypeptides and methods for their preparation aredescribed by Nora et al. (1998, Am J Physiol. 275(4 Pt 2):H1395-403),Yiu et al. (1997, Regul Pept. 70(1):15-21), Reagan et al. (1993, ProcNatl Acad Sci USA. 90(17):7956-7960), Rakugi et al. (1997, HypertensRes. 20(1):51-55) and Wang et al. (1998 Hypertension. 32(1):78-83), andsome are available commercially, such as but not limited to H-143 (SantaCruz Biotechnology, Santa Cruz, Calif.), which is directed against aminoacid residues 221-363 from the carboxy terminus of human AT₂, rAT2 (Ab#1), which is directed against an 18-residue C-terminal fragment of ratAT₂), rAT2 (Ab #2) which is directed against an 18-residue C-terminalfragment of rat AT₂) and rAT2 (Ab #3), which is directed against a10-residue N-terminal fragment of rat AT₂ (Alpha DiagnosticInternational, Inc.—5415 Lost Lane, SA).

In still other embodiments, the AT₂ receptor antagonist is selected fromnucleic acid molecules that inhibit or otherwise reduce the level orfunctional activity of an expression product of an AT₂ gene,illustrative examples of which include antisense molecules, ribozymesand RNAi molecules. Thus, the present invention contemplates antisenseRNA and DNA molecules as well as ribozymes and RNAi molecules thatfunction to inhibit the translation, for example, of Agtr2 mRNA.Antisense RNA and DNA molecules act to directly block the translation ofmRNA by binding to targeted mRNA and preventing protein translation. Inregard to antisense DNA, oligodeoxyribonucleotides derived from thetranslation initiation site, e.g., between −10 and +10 regions of anAgtr2 gene, are desirable. Exemplary antisense oligonucleotides can bederived from any nucleic acid molecule that encodes an AT₂ receptor,such as those described in U.S. Pat. No. 5,556,780, and in U.S. Pat.Appl. Pub. No. 20030083339. Therapeutic methods utilizing antisenseoligonucleotides have been described in the art, for example, in U.S.Pat. Nos. 5,627,158 and 5,734,033. Generally, antisense moleculescomprise from about 8 to about 30 bases (i.e., from about 8 to about 30linked nucleosides) and typically comprise from about 12 to about 25bases.

Ribozymes are enzymatic RNA molecules capable of catalyzing the specificcleavage of RNA. The mechanism of ribozyme action involves sequencespecific hybridization of the ribozyme molecule to complementary targetRNA, followed by an endonucleolytic cleavage. Within the scope of theinvention are engineered hammerhead motif ribozyme molecules thatspecifically and efficiently catalyze endonucleolytic cleavage of Agtr2RNA sequences. Specific ribozyme cleavage sites within any potential RNAtarget are initially identified by scanning the target molecule forribozyme cleavage sites which include the following sequences, GUA, GUUand GUC. Once identified, short RNA sequences of between 15 and 20ribonucleotides corresponding to the region of the target genecontaining the cleavage site may be evaluated for predicted structuralfeatures such as secondary structure that may render the oligonucleotidesequence unsuitable. The suitability of candidate targets may also beevaluated by testing their accessibility to hybridization withcomplementary oligonucleotides, using ribonuclease protection assays.

Both antisense RNA and DNA molecules and ribozymes may be prepared byany method known in the art for the synthesis of nucleic acid molecules.These include techniques for chemically synthesizingoligodeoxyribonucleotides well known in the art such as for examplesolid phase phosphoramidite chemical synthesis. Alternatively, RNAmolecules may be generated by in vitro and in vivo transcription of DNAsequences encoding the antisense RNA molecule. Such DNA sequences may beincorporated into a wide variety of vectors which incorporate suitableRNA polymerase promoters such as the T7 or SP6 polymerase promoters.Alternatively, antisense cDNA constructs that synthesize antisense RNAconstitutively or inducibly, depending on the promoter used, can beintroduced stably into cell lines.

Various modifications to nucleic acid molecules may be introduced as ameans of increasing intracellular stability and half-life. Possiblemodifications include but are not limited to the addition of flankingsequences of ribo- or deoxy-nucleotides to the 5′ and/or 3′ ends of themolecule or the use of artificial linkages rather than phosphodiesteraselinkages within the oligodeoxyribonucleotide backbone. Illustrativemodified oligonucleotide backbones include, for example,phosphorothioates, chiral phosphorothioates, phosphorodithioates,phosphotriesters, aminoalkylphosphotriesters, methyl and other alkylphosphonates including 3′-alkylene phosphonates and chiral phosphonates,phosphinates, phosphoramidates including 3′-amino phosphoramidate andaminoalkylphosphoramidates, thionophosphoramidates,thionoalkylphosphonates, thionoalkylphosphotriesters, andboranophosphates having normal 3′-5′ linkages, 2′-5′ linked analogs ofthese, and those having inverted polarity wherein the adjacent pairs ofnucleoside units are linked 3′-5′ to 5′-3′ or 2′-5′ to 5′-2′. Varioussalts, mixed salts and free acid forms are also included.

Other agents that may be used to decrease the expression of an Agtr2gene or the level and/or functional activity of an expression product ofthat gene include RNA molecules that mediate RNA interference (RNAi) ofa Agtr2 gene or gene transcript. RNAi refers to interference with ordestruction of the product of a target gene by introducing a singlestranded, and typically a double stranded RNA (dsRNA), which ishomologous to the transcript of the target gene. Thus, in oneembodiment, dsRNA per se and especially dsRNA-producing constructs thatencode an amino acid sequence corresponding to at least a portion of anAT₂ receptor polypeptide may be used to decrease its level and/orfunctional activity. RNAi-mediated inhibition of gene expression may beaccomplished using any of the techniques reported in the art, forinstance by transfecting a nucleic acid construct encoding a stem-loopor hairpin RNA structure into the genome of the target cell, or byexpressing a transfected nucleic acid construct having homology for atarget gene from between convergent promoters, or as a head to head ortail to tail duplication from behind a single promoter. Any similarconstruct may be used so long as it produces a single RNA having theability to fold back on itself and produce a dsRNA, or so long as itproduces two separate RNA transcripts which then anneal to form a dsRNAhaving homology to a target gene.

Absolute homology is not required for RNAi, with a lower threshold beingdescribed at about 85% homology for a dsRNA of about 200 base pairs(Plasterk and Ketting, 2000, Current Opinion in Genetics and Dev. 10:562-567). Therefore, depending on the length of the dsRNA, theRNAi-encoding nucleic acids can vary in the level of homology theycontain toward the target gene transcript, i.e., with dsRNAs of 100 to200 base pairs having at least about 85% homology with the target gene,and longer dsRNAs, i.e., 300 to 100 base pairs, having at least about75% homology to the target gene. RNA-encoding constructs that express asingle RNA transcript designed to anneal to a separately expressed RNA,or single constructs expressing separate transcripts from convergentpromoters, are preferably at least about 100 nucleotides in length.RNA-encoding constructs that express a single RNA designed to form adsRNA via internal folding are preferably at least about 200 nucleotidesin length.

The promoter used to express the dsRNA-forming construct may be any typeof promoter if the resulting dsRNA is specific for a gene product in thecell lineage targeted for destruction. Alternatively, the promoter maybe lineage specific in that it is only expressed in cells of aparticular development lineage. This might be advantageous where someoverlap in homology is observed with a gene that is expressed in anon-targeted cell lineage. The promoter may also be inducible byexternally controlled factors, or by intracellular environmentalfactors.

In another embodiment, RNA molecules of about 21 to about 23nucleotides, which direct cleavage of specific mRNA to which theycorrespond, as for example described by Tuschl et al. in U.S. Pat. Appl.Pub. No. 20020086356, can be utilized for mediating RNAi. Such 21-23 ntRNA molecules can comprise a 3′ hydroxyl group, can be single-strandedor double stranded (as two 21-23 nt RNAs) wherein the dsRNA moleculescan be blunt ended or comprise overhanging ends (e.g., 5′, 3′).

4. Identification of AT₂ Receptor Antagonists

The invention also features methods of screening for agents thatantagonize an AT₂ receptor, including reducing the expression of an AT₂gene (also known as an Agtr2 gene) or the level and/or functionalactivity of an expression product of that gene. Thus, a candidate agentidentified according to these methods has an ability to reduce thebiological activity or property of an AT₂ receptor polypeptide.

Candidate agents falling within the scope of the present inventioninclude antagonistic antigen-binding molecules, and inhibitor peptidefragments, antisense molecules, ribozymes, RNAi molecules andco-suppression molecules. Other candidate agents include small organiccompounds having a molecular weight of more than 50 and less than about2,500 Dalton and will typically comprise functional groups necessary forstructural interaction with proteins, particularly hydrogen bonding, andtypically include at least an amine, carbonyl, hydroxyl or carboxylgroup, suitably at least two of the functional chemical groups.Candidate agents often comprise cyclical carbon or heterocyclicstructures or aromatic or polyaromatic structures substituted with oneor more of the above functional groups. Candidate agents are also foundamong biomolecules including, but not limited to: peptides, saccharides,fatty acids, steroids, purines, pyrimidines, derivatives, structuralanalogues or combinations thereof.

Small (non-peptide) molecule AT₂ receptor antagonists are generallyadvantageous because such molecules are more readily absorbed after oraladministration, have fewer potential antigenic determinants, or are morelikely to cross the cell membrane than larger, protein-basedpharmaceuticals. Small organic molecules may also have the ability togain entry into an appropriate cell and affect the expression of a gene(e.g., by interacting with the regulatory region or transcriptionfactors involved in gene expression); or affect the activity of a geneby inhibiting or enhancing the binding of accessory molecules.

Alternatively, libraries of natural compounds in the form of bacterial,fungal, plant and animal extracts are available or readily produced.Additionally, natural or synthetically produced libraries and compoundsare readily modified through conventional chemical, physical andbiochemical means, and may be used to produce combinatorial libraries.Known pharmacological agents may be subjected to directed or randomchemical modifications, such as acylation, alkylation, esterification,amidification, etc to produce structural analogues.

Screening may also be directed to known pharmacologically activecompounds and chemical analogues thereof.

In some embodiments, the methods comprise: (1) contacting a preparationwith a test agent, wherein the preparation contains (i) a polypeptidecomprising an amino acid sequence corresponding to at least abiologically active fragment of an AT₂ receptor, or to a variant orderivative thereof; or (ii) a polynucleotide comprising at least aportion of a genetic sequence that regulates an AT₂ gene, which isoperably linked to a reporter gene; and (2) detecting a decrease in thelevel and/or functional activity of the polypeptide, or an expressionproduct of the reporter gene, relative to a normal or reference leveland/or functional activity in the absence of the test agent, whichindicates that the agent antagonizes the AT₂ receptor.

In illustrative examples of this type, the methods comprise the steps ofestablishing a control system comprising an AT₂ receptor polypeptide anda ligand which is capable of binding to the polypeptide; establishing atest system comprising an AT₂ receptor polypeptide, the ligand, and acandidate compound; and determining whether the candidate compoundinhibits or otherwise reduces the functional activity of the polypeptideby comparison of the test and control systems. Representative ligandscan comprise a compound according to any one of formulae I-VIII, and inthese embodiments, the functional activity screened can include bindingaffinity. In certain embodiments, the methods comprise (a) incubating anAT₂ receptor polypeptide with a ligand (e.g., angiotensin II) in thepresence of a test inhibitor compound; (b) determining an amount ofligand that is bound to the AT₂ receptor polypeptide, wherein decreasedbinding of ligand to the AT₂ receptor polypeptide in the presence of thetest inhibitor compound relative to binding in the absence of the testinhibitor compound is indicative of inhibition; and (c) identifying thetest compound as an AT₂ receptor antagonist if decreased ligand bindingis observed. In other embodiments, the methods comprise: (a) incubatinga cell membrane, which comprises an AT₂ receptor polypeptide, with afirst ligand (e.g., angiotensin II) in the presence of a test inhibitorcompound; (b) optionally blocking any AT₁ receptors present on or in themembrane with a second ligand that binds specifically to the AT₁receptor (e.g., losartan or candesartan) if the first ligand also bindsto the AT₁ receptor; (c) determining an amount of first ligand that isbound to the membrane, wherein decreased binding of ligand to themembrane in the presence of the test inhibitor compound relative tobinding in the absence of the test inhibitor compound is indicative ofinhibition; and (d) identifying the test compound as an AT₂ receptorantagonist if decreased first ligand binding is observed.

In other illustrative examples, a form of an AT₂ receptor polypeptide ora catalytic or immunogenic fragment or oligopeptide thereof, is used forscreening libraries of compounds in any of a variety of drug screeningtechniques. The fragment employed in such a screening can be affixed toa solid support. The formation of binding complexes, between an AT₂receptor polypeptide and the agent being tested, will be detected. Inspecific embodiments, an AT₂ receptor polypeptide comprises an aminoacid sequence corresponding to any one of:

[SEQ ID NO: 25] MKGNSTLATTSKNITSGLHFGLVNISGNNESTLNCSQKPSDKHLDAIPILYYLIIFVIGFLVNIVVVTLFCCQKGPKKVSSIYIFNLAVADLLLLATLPLWATYYSYRYDWLFGPVMCKVFGSFLTLNMFASIFFITCMSVDRYQSVIYPFLSQRRNPWQASYIVPLVWCMACLSSLPTFYFRDVRTIEYLGVNACIMAFPPEKYAQWSAGIALMKNILGFIIPLIFIATCYFGIRKHLLKTNSYGKNRITRDQVLKMAAAVVLAFIICWLPFHVLTFLDALAWMGVINSCEVIAVIDLALPFAILLGFTNSCVNPFLYCFVGNRFQQKLRSVERVPITWLQGKRESMSCRKSSSLREMETFVS (human AGTR2); [SEQ ID NO: 26]MKDNFSFAATSRNITSSRPFDNLNATGTNESAFNCSHKPSDKHLEAIPVLYYMIFVIGFAVNIVVVSLFCCQKGPKKVSSIYIFNLALADLLLLATLPLWATYYSYRYDWLFGPVMCKVFGSFLTLNMFASIFFITCMSVDRYQSVIYPFLSQRRNPWQASYVVPLVWCMACLSSLPTFYFRDVRTIEYLGVNACIMAFPPEKYAQWSAGIALMKNILGFIIPLIFIATCYFGIRKHLLKTNSYGKNRITRDQVLKMAAAVVLAFIICWLPFHVLTFLDALTWMGIINSCEVIAVIDLALPFAILLGFTNSCVNPFLYCFVGNRFQQKLRSVFRVPITWLQGKRETMSCRKGSSLREMDTFVS (murine AGTR2); and [SEQ ID NO: 27]MKDNFSFAATSRNITSSLPFDNLNATGTNESAFNCSHKPADKHLEAIPVLYYMIFVIGFAVNIVVVSLFCCQKGPKKVSSIYIFNLAVADLLLLATLPLWATYYSYRYDWLFGPVMCKVFGSFLTLNMFASIFFITCMSVDRYQSVIYPFLSQRRNPWQASYVVPLVWCMACLSSLPTFYFRDVRTIEYLGVNACIMAFPPEKYAQWSAGIALMKNILGFIIPLIFIATCYFGIRKHLLKTNSYGKNRITRDQVLKMAAAVVLAFIICWLPFHVLTFLDALTWMGIINSCEVIAVIDLALPFAILLGFTNSCVNPFLYCFVGNRFQQKLRSVFRVPITWLQGKRETMSCRKSSSLREMDTFVS (rat AGTR2).

In still other illustrative examples, a plurality of different smalltest compounds are synthesized on a solid substrate, such as plasticpins or some other surface. The test compounds are reacted with an AT₂receptor polypeptide, or fragments thereof. Bound polypeptide is thendetected by methods well known to those of skill in the art. Thepolypeptide can also be placed directly onto plates for use in theaforementioned drug screening techniques.

In other illustrative examples, the methods comprise: contacting an AT₂receptor polypeptide with individual members of a library of testsamples; detecting an interaction between a test sample and an AT₂receptor polypeptide; identifying a test sample that interacts with anAT₂ receptor polypeptide; and isolating a test sample that interactswith an AT₂ receptor polypeptide.

In each of the foregoing embodiments, an interaction can be detectedspectrophotometrically, radiologically or immunologically. Aninteraction between AT₂ receptor polypeptide and a test sample can alsobe quantified using methods known to those of skill in the art.

In still other embodiments, the methods comprise incubating a cell(e.g., an endothelial cell such as a coronary endothelial cell (CEC), aPC12W cell, a SK-UT-1 cell, a 3T3 fibroblast cell or a NG108-15 cell),which naturally or recombinantly expresses an AT₂ receptor on itssurface, in the presence and absence of a candidate agent underconditions in which the AT₂ receptor is able to bind an AT₂ receptorligand, and the level of AT₂ receptor activation is measured by asuitable assay. For example, an AT₂ receptor antagonist can beidentified by measuring the ability of a candidate agent to decrease AT₂receptor activation in the cell from a baseline value in the presence ofreceptor ligand. In illustrative examples, PC12W cells are exposed to,or cultured in the presence of angiotensin II and in the presence andabsence of, the candidate agent under conditions in which the AT₂receptor is active on the cells, and differentiation of the cells ismeasured. An agent tests positive for AT₂ receptor antagonism if itinhibits differentiation of the cells. In other illustrative examples,PC12W cells are exposed to, or cultured in the presence of angiotensinII and in the presence and absence of, the candidate agent underconditions in which the AT₂ receptor is active on the cells, and thelevel of nitric oxide or the level or functional activity of nitricoxide synthase in the cells is measured. An agent tests positive for AT₂receptor antagonism if it inhibits nitric oxide or the level orfunctional activity of nitric oxide synthase. In still otherillustrative examples, coronary endothelial cells are exposed to, orcultured in the presence of angiotensin II and in the presence andabsence of, the candidate agent under conditions in which the AT₂receptor is active on the cells, and expression of Zfhep, which is aprotein associated with cell differentiation, in the cells is measured.An agent tests positive for AT₂ receptor antagonism if it inhibits Zfhepexpression in the cells. In specific embodiments, any AT₁ receptors onthe surface of the cells is blocked using an AT₁ receptor ligand such aslosartan and candesartan.

5. Compositions

Another aspect of the present invention provides compositions fortreating, preventing and/or relieving the symptoms of inflammatory pain,comprising an effective amount of an AT₂ receptor antagonist and apharmaceutically acceptable carrier and/or diluent.

Any known AT₂ receptor antagonist can be used in the methods of thepresent invention, provided that the AT₂ receptor antagonist arepharmaceutically active. A “pharmaceutically active” AT₂ receptorantagonist is in a form which results in the treatment and/or preventionof inflammatory pain, including the prevention of incurring a symptom,holding in check such symptoms or treating existing symptoms associatedwith inflammatory pain, when administered to an individual.

The effect of compositions of the present invention may be examined byusing one or more of the published models of pain/nociception,especially of inflammatory pain, known in the art. This may bedemonstrated, for example using a model which assesses the onset anddevelopment of inflammatory pain. For example, there are several modelsthat rely on injecting a pro-inflammatory tissue irritant into the rathindpaw to induce hindpaw inflammation and testing whether theadministration of a test drug has anti-hyperalgesic (pain-relieving)efficacy. Illustrative methods of this type include the Randall Selittomethod (1957, Arch Int Pharmacodyn Ther 111: 409-419), which involvesinjection of a small volume (0.1 mL) of Brewer's yeast into the rathindpaw to induce hindpaw inflammation with the test drugs beingadministered by the subcutaneous route at the same time as the yeast isinjected into the hindpaw. Noxious pressure is then applied to theinflamed hindpaw of the rat and the ability of the test compounds toeither prevent the development of inflammation and/or to alleviateinflammatory pain is assessed. The pressure at which an escape responseis observed, is measured, for example, at 1, 2 and 4 h afteradministration of the test drug. Dose-response curves are constructedbased on the responses measured at 1 h post-dosing. The duration of theswelling hypersensitivity is between 24 and 48 h.

The Randall Selitto method has been modified by several groups in whichthe test drug is administered (e.g., 2 h) after injection of yeast intothe rat's hindpaw (Otterness and Bliven, 1985, Laboratory models fortesting non-steroidal anti-inflammatory drugs, in: Non-steroidalanti-inflammatory drugs, Lombardino, J. G. (Ed.), pp. 111-252.Wiley-Interscience, New York). The rationale for this change is that itis a more difficult challenge to alleviate inflammation that is alreadyestablished, compared with prevention of inflammation development.

Additional modifications to the Randall Selitto method include changingthe tissue irritant that is injected into the rat's hindpaw such thatdifferent irritants produce markedly different apparent responsivenessof the test drugs. Specifically, three classes of pro-inflammatorytissue irritants have been defined (Otterness and Bliven, 1985, supra),as follows:

(i) agents such as carrageenan and kaolin which produce hindpawinflammation in the rat that is highly sensitive to anti-inflammatorydrugs but insensitive to anti-serotonin drugs.

(ii) agents such as trypsin and elastase that are relatively insensitiveto anti-inflammatory and anti-serotonin drugs.

(iii) agents such as dextran, hyaluronidase, acid phosphatase andserotonin that are highly sensitive to anti-serotonin agents andinsensitive to anti-inflammatory agents.

Oedema produced by an injection of yeast into the rat hindpaw isgenerally regarded as being a hybrid of types (ii) and (iii) above(Otterness and Bliven, 1985). Although NSAIDs have been shown toeffectively alleviate yeast-induced inflammatory pain in the rathindpaw, NSAIDs have little effect on yeast-induced swelling. However,anti-serotonin agents effectively reduce yeast-induced swelling andinflammatory pain in the rat hindpaw (Otterness and Bliven, 1985).

Another method based in part on the modified Randall Selitto methodsnoted above uses Freund's complete adjuvant (FCA) as the inflammatorytissue irritant as described for instance in Example 1.

The active compounds of the present invention may be provided as saltswith pharmaceutically compatible counterions. Pharmaceuticallycompatible salts refer to those salts which are, within the scope ofsound medical judgment, suitable for use in contact with the tissues ofhumans and lower animals without undue toxicity, irritation, allergicresponse and the like, and are commensurate with a reasonablebenefit/risk ratio. Pharmaceutically compatible salts are well known inthe art. For example, S. M. Berge, et al. describe pharmaceuticallycompatible salts in detail in J. Pharmaceutical Sciences, 66: 1-19(1977). The salts can be prepared in situ during the final isolation andpurification of the active compounds of the invention, or separately byreacting the free base function with a suitable organic acid. Examplesof pharmaceutically compatible, non-toxic acid addition salts are saltsof an amino group formed with inorganic acids such as hydrochloric acid,hydrobromic acid, phosphoric acid, sulfuric acid and perchloric acid orwith organic acids such as acetic acid, oxalic acid, maleic acid,tartaric acid, citric acid, succinic acid or malonic acid or by usingother methods used in the art such as ion exchange. Otherpharmaceutically compatible salts include adipate, alginate, ascorbate,aspartate, benzenesulfonate, benzoate, bisulfate, borate, butyrate,camphorate, camphorsulfonate, citrate, cyclopentanepropionate,digluconate, dodecylsulfate, ethanesulfonate, formate, fumarate,glucoheptonate, glycerophosphate, gluconate, hemisulfate, heptanoate,hexanoate, hydroiodide, 2-hydroxy-ethanesulfonate, lactobionate,lactate, laurate, lauryl sulfate, malate, maleate, malonate,methanesulfonate, 2-naphthalenesulfonate, nicotinate, nitrate, oleate,oxalate, palmitate, pamoate, pectinate, persulfate, 3-phenylpropionate,phosphate, picrate, pivalate, propionate, stearate, succinate, sulfate,tartrate, thiocyanate, p-toluenesulfonate, undecanoate, valerate salts,and the like. Representative alkali or alkaline earth metal saltsinclude sodium, lithium, potassium, calcium, magnesium, and the like.Further pharmaceutically compatible salts include, when appropriate,non-toxic ammonium, quaternary ammonium, and amine cations formed usingcounterions such as halide, hydroxide, carboxylate, sulfate, phosphate,nitrate, lower alkyl sulfonate and aryl sulfonate.

Pharmaceutical compositions suitable for use in the present inventioninclude compositions wherein the pharmaceutically active compounds arecontained in an effective amount to achieve their intended purpose. Thedose of active compounds administered to a patient should be sufficientto achieve a beneficial response in the patient over time such as areduction in at least one symptom associated with inflammatory pain. Thequantity of the pharmaceutically active compounds(s) to be administeredmay depend on the subject to be treated inclusive of the age, sex,weight and general health condition thereof. In this regard, preciseamounts of the active compound(s) for administration will depend on thejudgement of the practitioner. In determining the effective amount ofthe active compound(s) to be administered in the treatment orprophylaxis of inflammatory pain, the physician may evaluate the levelor amount of swelling, redness, hyperalgesia (e.g., mechanical andthermal hyperalgesia), and allodynia in, or experienced by, the subject.In any event, those of skill in the art may readily determine suitabledosages of the AT₂ receptor antagonists of the invention.

An effective amount of an AT₂ receptor antagonist is one that iseffective for treating or preventing the symptoms associated withinflammatory pain, including the prevention of incurring a symptom,holding in check such symptoms, and/or treating existing symptomsassociated with inflammatory pain. Modes of administration, amounts ofAT₂ receptor antagonist administered, and AT₂ receptor antagonistformulations, for use in the methods of the present invention, arediscussed below. Whether the inflammatory pain has been treated isdetermined by measuring one or more diagnostic parameters indicative ofthe course of the disease, compared to a suitable control. In the caseof an animal experiment, a “suitable control” is an animal not treatedwith the AT₂ receptor antagonist, or treated with the pharmaceuticalcomposition without the AT₂ receptor antagonist. In the case of a humansubject, a “suitable control” may be the individual before treatment, ormay be a human (e.g., an age-matched or similar control) treated with aplacebo. In accordance with the present invention, the treatment of painincludes and encompasses without limitation: (i) preventing painexperienced by a subject which may be predisposed to the condition buthas not yet been diagnosed with the condition and, accordingly, thetreatment constitutes prophylactic treatment for the pathologiccondition; (ii) inhibiting pain initiation or a painful condition, i.e.,arresting its development; (iii) relieving pain, i.e., causingregression of pain initiation or a painful condition; or (iv) relievingsymptoms resulting from a disease or condition believed to cause pain,e.g., relieving the sensation of pain without addressing the underlyingdisease or condition.

The methods of the present invention are suitable for treating anindividual who has been diagnosed with inflammatory pain, who issuspected of having inflammatory pain, who is known to be susceptibleand who is considered likely to develop inflammatory pain, or who isconsidered likely to develop a recurrence of a previously treatedinflammatory pain.

In some embodiments, and dependent on the intended mode ofadministration, the AT₂ receptor antagonist-containing compositions willgenerally contain about 0.000001% to 90%, about 0.0001% to 50%, or about0.01% to about 25%, by weight of AT₂ receptor antagonist, the remainderbeing suitable pharmaceutical carriers or diluents etc. The dosage ofthe AT₂ receptor antagonist can depend on a variety of factors, such asmode of administration, the species of the affected subject, age and/orindividual condition, and can be easily determined by a person of skillin the art using standard protocols.

Depending on the specific inflammatory pain being treated, the activecompounds may be formulated and administered systemically, topically orlocally. Techniques for formulation and administration may be found in“Remington's Pharmaceutical Sciences,” Mack Publishing Co., Easton, Pa.,latest edition. Suitable routes may, for example, include oral, rectal,transmucosal, or intestinal administration; parenteral delivery,including intramuscular, subcutaneous, intramedullary injections, aswell as intrathecal, direct intraventricular, intravenous,intraperitoneal, inhaled, intranasal, or intraocular injections. Forinjection, the therapeutic agents of the invention may be formulated inaqueous solutions, suitably in physiologically compatible buffers suchas Hanks' solution, Ringer's solution, or physiological saline buffer.For transmucosal administration, penetrants appropriate to the bather tobe permeated are used in the formulation. Such penetrants are generallyknown in the art.

Alternatively, the compositions of the invention can be formulated forlocal or topical administration. In this instance, the subjectcompositions may be formulated in any suitable manner, including, butnot limited to, creams, gels, oils, ointments, solutions andsuppositories. Such topical compositions may include a penetrationenhancer such as benzalkonium chloride, digitonin, dihydrocytochalasinB, capric acid, increasing pH from 7.0 to 8.0. Penetration enhancerswhich are directed to enhancing penetration of the active compoundsthrough the epidermis are preferred in this regard. Alternatively, thetopical compositions may include liposomes in which the active compoundsof the invention are encapsulated.

The compositions of this invention may be formulated for administrationin the form of liquids, containing acceptable diluents (such as salineand sterile water), or may be in the form of lotions, creams or gelscontaining acceptable diluents or carriers to impart the desiredtexture, consistency, viscosity and appearance. Acceptable diluents andcarriers are familiar to those skilled in the art and include, but arenot restricted to, ethoxylated and nonethoxylated surfactants, fattyalcohols, fatty acids, hydrocarbon oils (such as palm oil, coconut oil,and mineral oil), cocoa butter waxes, silicon oils, pH balancers,cellulose derivatives, emulsifying agents such as non-ionic organic andinorganic bases, preserving agents, wax esters, steroid alcohols,triglyceride esters, phospholipids such as lecithin and cephalin,polyhydric alcohol esters, fatty alcohol esters, hydrophilic lanolinderivatives, and hydrophilic beeswax derivatives.

Alternatively, the active compounds of the present invention can beformulated readily using pharmaceutically acceptable carriers well knownin the art into dosages suitable for oral administration, which is alsopreferred for the practice of the present invention. Such carriersenable the compounds of the invention to be formulated in dosage formssuch as tablets, pills, capsules, liquids, gels, syrups, slurries,suspensions and the like, for oral ingestion by a patient to be treated.These carriers may be selected from sugars, starches, cellulose and itsderivatives, malt, gelatine, talc, calcium sulfate, vegetable oils,synthetic oils, polyols, alginic acid, phosphate buffered solutions,emulsifiers, isotonic saline, and pyrogen-free water.

Pharmaceutical formulations for parenteral administration includeaqueous solutions of the active compounds in water-soluble form.Additionally, suspensions of the active compounds may be prepared asappropriate oily injection suspensions. Suitable lipophilic solvents orvehicles include fatty oils such as sesame oil, or synthetic fatty acidesters, such as ethyl oleate or triglycerides, or liposomes. Aqueousinjection suspensions may contain substances that increase the viscosityof the suspension, such as sodium carboxymethyl cellulose, sorbitol, ordextran. Optionally, the suspension may also contain suitablestabilizers or agents that increase the solubility of the compounds toallow for the preparation of highly concentrated solutions.

Pharmaceutical preparations for oral use can be obtained by combiningthe active compounds with solid excipients, optionally grinding aresulting mixture, and processing the mixture of granules, after addingsuitable auxiliaries, if desired, to obtain tablets or dragee cores.Suitable excipients are, in particular, fillers such as sugars,including lactose, sucrose, mannitol, or sorbitol; cellulosepreparations such as, for example, maize starch, wheat starch, ricestarch, potato starch, gelatine, gum tragacanth, methyl cellulose,hydroxypropylmethyl-cellulose, sodium carboxymethylcellulose, and/orpolyvinylpyrrolidone (PVP). If desired, disintegrating agents may beadded, such as the cross-linked polyvinyl pyrrolidone, agar, or alginicacid or a salt thereof such as sodium alginate. Such compositions may beprepared by any of the methods of pharmacy but all methods include thestep of bringing into association one or more therapeutic agents asdescribed above with the carrier which constitutes one or more necessaryingredients. In general, the pharmaceutical compositions of the presentinvention may be manufactured in a manner that is itself known, eg. bymeans of conventional mixing, dissolving, granulating, dragee-making,levigating, emulsifying, encapsulating, entrapping or lyophilizingprocesses.

Dragee cores are provided with suitable coatings. For this purpose,concentrated sugar solutions may be used, which may optionally containgum arabic, talc, polyvinyl pyrrolidone, carbopol gel, polyethyleneglycol, and/or titanium dioxide, lacquer solutions, and suitable organicsolvents or solvent mixtures. Dyestuffs or pigments may be added to thetablets or dragee coatings for identification or to characterizedifferent combinations of active compound doses.

Pharmaceuticals which can be used orally include push-fit capsules madeof gelatine, as well as soft, sealed capsules made of gelatine and aplasticiser, such as glycerol or sorbitol. The push-fit capsules cancontain the active ingredients in admixture with filler such as lactose,binders such as starches, and/or lubricants such as talc or magnesiumstearate and, optionally, stabilizers. In soft capsules, the activecompounds may be dissolved or suspended in suitable liquids, such asfatty oils, liquid paraffin, or liquid polyethylene glycols. Inaddition, stabilizers may be added.

Dosage forms of the active compounds of the invention may also includeinjecting or implanting controlled releasing devices designedspecifically for this purpose or other forms of implants modified to actadditionally in this fashion. Controlled release of an active compoundof the invention may be achieved by coating the same, for example, withhydrophobic polymers including acrylic resins, waxes, higher aliphaticalcohols, polylactic and polyglycolic acids and certain cellulosederivatives such as hydroxypropylmethyl cellulose. In addition,controlled release may be achieved by using other polymer matrices,liposomes and/or microspheres.

The active compounds of the invention may be administered over a periodof hours, days, weeks, or months, depending on several factors,including the severity of the inflammatory pain being treated, whether arecurrence of the inflammatory pain is considered likely, etc. Theadministration may be constant, e.g., constant infusion over a period ofhours, days, weeks, months, etc. Alternatively, the administration maybe intermittent, e.g., active compounds may be administered once a dayover a period of days, once an hour over a period of hours, or any othersuch schedule as deemed suitable.

The compositions of the present invention may also be administered tothe respiratory tract as a nasal or pulmonary inhalation aerosol orsolution for a nebuliser, or as a microfine powder for insufflation,alone or in combination with an inert carrier such as lactose, or withother pharmaceutically acceptable excipients. In such a case, theparticles of the formulation may advantageously have diameters of lessthan 50 micrometers, suitably less than 10 micrometers.

The AT₂ receptor antagonists may be provided alone or in combinationwith other compounds such as those that are useful in the control ofinflammatory conditions. Illustrative compounds of this type include butare not restricted to non-steroidal anti-inflammatory compounds such ascelecoxib, diflunisal, fenoprofen, indomethacin, ketoprofen,meclofenamin acid, naproxen, acyclovir, phenylbutazone, piroxicam,salsalate, sulindac, tolectin, rofecoxib, valdecoxib, and combinationsof any two or more thereof. In some embodiments, the anti-inflammatorycompounds are selected from: (a) Leukotriene biosynthesis inhibitors,5-lipoxygenase (5-LO) inhibitors, and 5-lipoxygenase activating protein(FLAP) antagonists; (b) Receptor antagonists for leukotrienes LTB₄,LTC₄, LTD₄, and LTE₄; (c) 5-Lipoxygenase (5-LO) inhibitors and5-lipoxygenase activating protein (FLAP) antagonists; (d) Dualinhibitors of 5-lipoxygenase (5-LO) and antagonists of plateletactivating factor (PAF); (e) Leukotriene antagonists (LTRAS) of LTB₄,LTC₄, LTD₄, and LTE₄; (f) Antihistaminic H₁ receptor antagonists; (g)Gastroprotective H₂ receptor antagonists; (h) α₁- and α₂-adrenoceptoragonist vasoconstrictor sympathomimetic agents administered orally ortopically for decongestant use; (i) one or more α₁- and α₂-adrenoceptoragonists as recited in (h) above in combination with one or moreinhibitors of 5-lipoxygenase (5-LO) as recited in (a) above; (j)Theophylline and aminophylline; (k) Sodium cromoglycate; (1) Muscarinicreceptor (M1, M2, and M3) antagonists; (m) COX-1 inhibitors (NTHEs); andnitric oxide NTHEs; (n) COX-2 selective inhibitors; (o) COX-3 inhibitor;(p) insulin-like growth factor type I (IGF-1) mimetics; (q) Ciclesonide;(r) Corticosteroids; (s) Tryptase inhibitors; (t) Platelet activatingfactor (PAF) antagonists; (u) Monoclonal antibodies active againstendogenous inflammatory entities; (v) IPL 576; (w) Anti-tumor necrosisfactor (TNF-α) agents; (x) DMARDs; (y) Elastase inhibitors; (z) TCRpeptides; (aa) Interleukin converting enzyme (ICE) inhibitors; (bb)IMPDH inhibitors; (cc) Adhesion molecule inhibitors including VLA-4antagonists; (dd) Cathepsins; (ee) Mitogen activated protein kinase(MAPK) inhibitors; (ff) Mitogen activated protein kinase kinase (MAPKK)inhibitors; (gg) Glucose-6 phosphate dehydrogenase inhibitors; (hh)Kinin-B.sub.1- and B.sub.2-receptor antagonists; (ii) Gold in the formof an aurothio group in combination with hydrophilic groups; (jj)Immunosuppressive agents; (Irk) Anti-gout agents; (ll) Xanthine oxidaseinhibitors; (mm) Uricosuric agents; (nn) Antineoplastic agents that areantimitotic drugs; (oo) Growth hormone secretagogues; (pp) Inhibitors ofmatrix metalloproteinases (MMPs); (qq) Transforming growth factor(TGF.beta.); (rr) Platelet-derived growth factor (PDGF); (ss) Fibroblastgrowth factor; (tt) Granulocyte macrophage colony stimulating factor(GM-CSF); (uu) Capsaicin; and (vv) Tachykinin NX₁ and NK₃ receptorantagonists. Non-limiting examples of this type are wherein: (a) theLeukotriene biosynthesis inhibitors, 5-lipoxygenase (5-LO) inhibitors,and 5-lipoxygenase activating protein (FLAP) antagonists are selectedfrom the group consisting of zileuton; ABT-761; fenleuton; tepoxalin;Abbott-79175; Abbott-85761;N-(5-substituted)-thiophene-2-alkylsulfonamides; 2,6-di-tert-butylphenolhydrazones; Zeneca ZD-2138; SB-210661; pyridinyl-substituted2-cyanonaphthalene compound L-739,010; 2-cyanoquinoline compoundL-746,530; indole and quinoline compounds MK-591, MK-886, and BAY×1005;(b) the receptor antagonists for leukotrienes LTB₄, LTC₄, LTD₄, and LTE₄antagonists are selected from the group consisting of phenothiazin-3-onecompound L-651,392; amidino compound CGS-25019c; benzoxazolaminecompound ontazolast; benzenecarboximidamide compound BILL 284/260;compounds zafirlukast, ablukast, montelukast, pranlukast, verlukast(MK-679), RG-12525, Ro-245913, iralukast (CGP 45715A), and BAY×7195; (f)the antihistaminic H₁ receptor antagonists antagonists are selected fromthe group consisting of cetirizine, loratadine, desloratadine,fexofenadine, astemizole, azelastine, and chlorpheniramine; (h) α₁- andα₂-adrenoceptor agonist vasoconstrictor sympathomimetic agents areselected from the group consisting of propylhexedrine, phenylephrine,phenylpropanolamine, pseudoephedrine, naphazoline hydrochloride,oxymetazoline hydrochloride, tetrahydrozoline hydrochloride,xylometazoline hydrochloride, and ethylnorepinephrine hydrochloride; (n)the COX-2 selective inhibitor are selected from the group consisting ofrofecoxib and celecoxib; (o) the COX-3 inhibitor is acetaminophen; (r)the Corticosteroids are selected from the group consisting ofprednisone, methylprednisone, triamcinolone, beclomethasone,fluticasone, budesonide, hydrocortisone, dexamethasone, mometasonefuroate, azmacort, betamethasone, beclovent, prelone, prednisolone,flunisolide, triamcinolone acetonide, beclomethasone dipropionate,fluticasone propionate, mometasone furoate, solumedrol and salmeterol;(w) the anti-tumor necrosis factor (TNF-.alpha.) agents selected fromthe group consisting of etanercept, infliximab, and D2E7; (x) the DMARDsis leflunomide; (y) the Elastase inhibitors are selected from the groupconsisting of UT-77 and ZD-0892; (jj) the Immunosuppressive agentsselected from the group consisting of cyclosporine, azathioprine,tacrolimus, and methotrexate; (kk) the anti-gout agents is colchicine;(ll) the Xanthine oxidase inhibitor is allopurinol; (mm) the Uricosuricagents are selected from the group consisting of probenecid,sulfinpyrazone, and benzbromarone; (nn) the antineoplastic agents areselected from the group consisting of vinblastine, vincristine,cyclophosphamide, and hydroxyurea; (pp) the inhibitors of matrixmetalloproteinases (MMPs) are selected from the group consisting ofstromelysins, the collagenases, the gelatinases, aggrecanase,collagenase-1 (MMP-1), collagenase-2 (MMP-8), collagenase-3 (MMP-13),stromelysin-1 (MMP-3), stromelysin-2 (MMP-10), and stromelysin-3(MMP11); and, (vv) the Tachykinin NK.sub.1 and NK.sub.3 receptorantagonists are selected from the group consisting of NKP-608C;SB-233412 (talnetant); and D-4418.

In order that the invention may be readily understood and put intopractical effect, particular preferred embodiments will now be describedby way of the following non-limiting examples.

EXAMPLES Example 1 PD-123,319 Produces Dose-Dependent Relief ofMechanical Hyperalgesia in the Inflamed Hindpaw of the FCA-Rat Model ofInflammatory Pain

Single bolus doses of PD-123,319 were administered by the i.p. route torats with FCA-induced unilateral hindpaw inflammation, a rat model ofinflammatory pain. Anti-hyperalgesic (pain-relieving) efficacy wasassessed using the Paw Pressure Test, a test which involves theapplication of noxious pressure to the inflamed hindpaw.

The results shown in FIG. 1 clearly show that PD-123,319 produceddose-dependent relief of mechanical hyperalgesia in the ipsilateral(inflamed) hindpaw of the FCA-rat model of inflammatory pain.

Materials and Methods Reagents and Materials

Isoflurane (Forthane®) was purchased from Abbott Australasia Pty Ltd(Sydney, Australia). Normal saline ampoules were obtained from DeltaWest Pty Ltd (Perth, Australia) and Abbott Australasia (Sydney,Australia). Dimethyl sulfoxide (DMSO) was purchased from Sigma Aldrich(Australia). Medical grade O₂ and CO₂ were purchased from BOC GasesAustralia Ltd (Brisbane, Australia). PD-123,319, as described in U.S.Pat. No. 4,812,462, was synthesized in the laboratory of Dr CraigWilliams, Dept of Chemistry, The University of Queensland (Brisbane,Australia).

Animals

Adult male Sprague-Dawley rats were purchased from the Herston MedicalResearch Centre, The University of Queensland. Rats were housed in atemperature controlled environment (21±2° C.) with a 12 h/12 hlight/dark cycle. Food and water were available ad libitum. Rats weregiven an acclimatization period of at least 3 days prior to initiationof experimental procedures. Ethical approval for this study was obtainedfrom the Animal Experimentation Ethics Committee of The University ofQueensland.

FCA-Rat Model of Inflammatory Pain

Hindpaw inflammation was induced by the i.pl. injection of 150 μL of thetissue irritant, Freund's complete adjuvant (FCA), into the left hindpawof adult male rats whilst they were anaesthetized with 3% isoflurane:97%oxygen. Following i.pl. FCA injection, the hindpaw volume increasedapproximately 1.5-2 fold over a 2-3 day period and this persisted forthe study duration. This type of persistent tissue injury iswell-documented to produce neuroplastic changes in the peripheral andcentral nervous systems, resulting in the development of thermalhyperalgesia (exaggerated response to the application of a noxiousthermal stimulus). The ability of single bolus doses of PD-123,319(˜7-70 mg/kg) or vehicle to alleviate mechanical hyperalgesia in theipsilateral (inflamed) hindpaw was assessed using the Paw Pressure Test(PPT). The contralateral (non-inflamed) hindpaw of the same animalserved as an internal control.

Paw Pressure Threshold's (FFT)

Rats were gently restrained with a towel and noxious pressure wasapplied to each of the ipsilateral (inflamed) and the contralateral(non-inflamed) hindpaws using a Ugo Basile Analgesiometer. When the ratsfelt pain, they were able to freely withdraw their hindpaw. TheAnalgesiometer had a maximum cut-off of 250 g pressure to avoid tissuedamage to the hindpaws when the rats' responses to the noxiousmechanical stimulus were depressed by the test article. Paw pressuretesting (PPT) was performed prior to i.pl. FCA administration and afterday 4 post-FCA. Additionally, following administration of single i.p.bolus doses of PD-123,319 or vehicle, PPT's were quantified at thefollowing times: pre-dose, 0.08, 0.25, 0.5, 0.75, 1, 1.5, 2, 3 hpost-dosing.

Example 2 Inflammatory Pain Model Induction of Mechanical Hyperalgesia

Mechanical hyperalgesia developed in the ipsilateral (inflamed), but notthe contralateral, hindpaw of rats following the i.pl. administration ofFCA into one hindpaw. Specifically, the mean (±SEM) paw pressurethresholds (PPTs) for the ipsilateral hindpaw decreased significantly(p<0.05) from 117.1 (±0.8) g to 62.4 (±1.2) g by 5 days post-FCAadministration. The mean (±SEM) PPT value for the contralateral hindpawdid not differ significantly (p>0.05) between that determined prior toFCA administration at 118.7 (±0.8) g and that determined 5 days later at120.6 (±1.5) g in the same animals (FIG. 2).

Paw Volume

Administration of FCA also increased the volume of the ipsilateralhindpaw, as expected. Specifically, the mean (±SEM) paw volume for theipsilateral hindpaw increased significantly (p<0.05) from 1.9 (±0.04)mLto 3.2 (±0.04) mL by 5 days post-FCA administration (FIG. 3).

The Anti-Hyperalgesic Effect of EMA Compounds in FCA-Rats

Administration of single i.p. bolus doses of EMA500 (sodium salt ofL-161,638) (1 to 100 mg/kg) in FCA-rats, appeared to producedose-dependent anti-hyperalgesia in the ipsilateral hindpaw (FIG. 4).For the doses tested, peak anti-hyperalgesia in the ipsilateral hindpawoccurred at approximately 0.5 h post-dosing and the correspondingduration of action was greater than 2 h at the highest dose tested (FIG.4A). Specifically, at the highest dose tested (100 mg/kg), the mean(±SD) peak PPT increased from 61.7 (±4.7) g pre-dose to 150 (±0) g at0.5 h post administration. Only at the highest dose tested (100 mg/kg)did EMA500 fully reverse mechanical hyperalgesia in FCA-rats.Administration of EMA500 in doses up to 100 mg/kg in FCA-rats producedinsignificant antinociception in the contralateral hindpaw (FIG. 4B).

Following i.p. administration of single bolus doses of EMA600(L-163,579) (1 to 100 mg/kg) in FCA-rats, there appeared to bedose-dependent anti-hyperalgesia produced in the ipsilateral hindpaw(FIG. 5). For the doses tested, peak anti-hyperalgesia in theipsilateral hindpaw occurred at approximately 0.5-1 h post-dosing andthe corresponding duration of action was approximately 1.5 h at thehighest dose tested (FIG. 5A). Specifically, at the highest dose tested(100 mg/kg), the mean (±SEM) peak PPT increased from 70.7 (±3.3) gpre-dose to 94.0 (±7.3) g at 0.75 h post administration. Administrationof EMA600 in doses up to 100 mg/kg in FCA-rats produced insignificantantinociception in the contralateral hindpaw (FIG. 5B).

As expected, single bolus s.c. doses of morphine at 0.5 mg/kg producedan anti-hyperalgesic response which peaked at 0.5 h post-dosing, with aduration of action of approximately 2-3 h. Specifically, the mean (±SEM)PPT increased from 63.7 (±2.5) g pre-dosing to 115.0 (±10.6) g at thetime of peak effect, demonstrating that morphine fully reversedFCA-induced mechanical hyperalgesia at 0.5 h post-dosing (FIGS. 3A and4A). Additionally, morphine at 0.5 mg/kg produced a smallantinociceptive effect in the contralateral hindpaw, but this did notreach statistical significance (p>0.05) (FIGS. 4B and 5B).

As expected, i.p. administration of vehicle did not produceanti-hyperalgesia or antinociception in the ipsilateral or contralateralhindpaws, respectively (FIGS. 4 and 5).

The Effect of EMA Compounds on Hindpaw Volume in FCA-Rats

Single bolus doses of EMA500, EMA600, morphine or vehicle did not alteripsilateral hindpaw volumes at 3 h post-dosing (FIG. 6).

Discussion

Following i.p. administration of single bolus doses of EMA500 at 10 to100 mg/kg, there was a dose-dependent relief of mechanical hyperalgesia(reversal) in the ipsilateral hindpaw which peaked at 0.5 h post-dosingwith a duration of action of ˜2 h. Following i.p. administration ofsingle bolus doses of EMA600 at 100 mg/kg in FCA-rats, there wassignificant relief of mechanical hyperalgesia (˜50% reversal) at thetime of peak effect post-dosing. Administration of EMA500 (1-100 mg/kg)and EMA600 (1-100 mg/kg) in FCA-rats produced insignificantantinociception in the contralateral hindpaw.

Consistent with expectations, i.p. administration of vehicle did notresult in significant relief of mechanical hyperalgesia in theipsilateral hindpaw of FCA-rats, confirming that neither the surgicalprocedures nor the vehicle in which the test articles were dissolved,significantly alleviated mechanical hyperalgesia in the ipsilateralhindpaw of FCA-rats.

Paw volumes at 3 h post-dosing were unaffected by either EMA500, EMA600or morphine at the doses tested.

Single i.p. bolus doses of EMA500 (1-100 mg/kg), EMA600 (1-30 mg/kg),morphine (0.5 mg/kg) and vehicle did not produce adverse behaviouraleffects in FCA-rats. However, single i.p. bolus doses of EMA600 at 100mg/kg produced abnormal gait and abdominal retraction for 5-15 minpost-dosing, suggestive of irritation in the peritoneal cavity at thisdose.

Methods Experimental Animals

Ethical approval for this study was obtained from the AnimalExperimentation Ethics Committee of The University of Queensland. Adultmale Sprague-Dawley (SD) rats (270±3 g at the time of FCA injection),were used in this study. Rats were housed in a temperature controlledroom (21±2.0° C.) with a 12 h/12 h fight/dark cycle. Food and water wereavailable ad libitum.

Drugs and Materials

Medical grade O2 and CO2 were purchased from BOC Gases Australia Ltd(Brisbane, Australia). Isoflurane (Isoflo™) was purchased from AbbottAustralasia (Sydney, Australia) Dimethyl sulfoxide (DMSO; lot#055K01033) and Freund's complete adjuvant (FCA) was purchased fromSigma-Aldrich (Sydney, Australia). Minivials (Eppendorf™) were purchasedfrom Disposable Products (Brisbane, Australia). Morphine hydrochloridewas from David Bull Laboratories (Melbourne, Australia).

Compounds for Administration Test Articles

EMA500 (Lot# CHM502) and EMA600 (Lot# ALC 49-50-SPM151) were supplied byGlycoSyn, a business unit of Industrial Research Limited (New Zealand).EMA500, which is the sodium salt of L-161,638 (L-161,638 is described byGlinka et al. 1994, Bioorg. Med. Chem. Lett. 4:1479 and in U.S. Pat. No.5,204,354) was synthesised as described in WO2006/066361. EMA600(L-163,579) was synthesized as described by Glinka et al. (1994, Bioorg.Med. Chem. Lett. 4:2337) and in U.S. Pat. No. 5,441,959. EMA500 andEMA600 were supplied in powder form and were stored at room temperature.Stock solutions for EMA500 and EMA600 were made freshly each morning ofevery dosing day.

Positive Control

Single bolus s.c. doses of morphine at 0.5 mg/kg were utilised as thepositive control for this study in FCA-rats.

Vehicle

The vehicle used to dissolve the Test Articles in this study was a90%:10% mixture of DMSO:water, whereas sterile water for injection wasthe vehicle used for the positive control (morphine).

Experimental Protocol FCA-Rat Model of Inflammatory Pain

Hindpaw inflammation was induced by the intraplantar (i.pl.) injectionof 150 μL of the tissue irritant, Freund's complete adjuvant (FCA), intothe left hindpaw of adult male rats, whilst they were anaesthetized with3% isoflurane:97% oxygen (O2). Following FCA injection, the hindpawvolume increased by 1.5-2 fold over a 2-3 day period and this persistedfor the study duration. This type of persistent tissue injury iswell-documented to produce neuroplastic changes in the peripheral andcentral nervous systems, resulting in the development of hyperalgesia(exaggerated response to the application of a noxious stimulus such aspressure in the ipsilateral (inflamed) hindpaw). The ability of singlebolus doses of EMA500 and EMA600 to alleviate mechanical hyperalgesia(noxious pressure) was assessed using the Paw Pressure Test (see belowfor details). The contralateral (non-inflamed) hindpaw of the sameanimal served as an internal control.

Pharmacodynamic Assessment Paw Pressure Thresholds (PPT)

Rats were gently restrained with a towel and noxious pressure wasapplied to each of the ipsilateral (inflamed) and the contralateral(non-inflamed) hindpaws using a Ugo Basile Analgesiometer. When the ratsfelt pain, they were able to freely withdraw their hindpaw. TheAnalgesiometer had a maximum cut-off of 250 g of pressure to avoidtissue damage to the hindpaws when the rats' responses to the noxiousmechanical stimulus were depressed by the test article. Hyperalgesia isregarded as being fully developed when PFTs in the ipsilateral hindpaware ≦80 g, whereas for non-injured rats the baseline PPTs in thehindpaws are ˜120 g. Restoring PPTs in the ipsilateral hindpaw from ≦80g to pre-FCA levels (˜120 g) is the treatment goal representing fullreversal of mechanical hyperalgesia.

Paw pressure testing was performed prior to i.pl. FCA administration,and on day 5 post-FCA, and at the following times: pre-dose and 0.25,0.5, 0.75, 1, 1.25, 1.5, 2 and 3 h post-dosing.

Paw Volume Measurement

Paw volume was assessed using displacement of water by the hindpaw toindicate the paw volume. These measurements were undertaken for both theipsilateral and contralateral hindpaws prior to and 5 days after i.pl.FCA administration and prior to and 3 h post-dosing.

Test Article Administration

Single bolus doses of EMA500, EMA600 and vehicle were administered bythe i.p. route and paw withdrawal thresholds in the hindpaws wereassessed using a Ugo Basile Analgesiometer in order to assess theanti-hyperalgesic efficacy of EMA500 and EMA600 in the injured(ipsilateral) hindpaw of FCA-rats. Similarly, single bolus doses ofmorphine were administered by the s.c. route to drug-naïve FCA-rats.

Behavioural Observations

The animals were monitored for visible and audible signs of distressthroughout the testing period. The visible signs of distress includedbehavioural changes such as complete immobility, movement with abnormalgait, agitation, aggression, wet dog shakes, excessive grooming,restlessness with constant movement, repeated sudden movements orstaring.

Rat Euthanasia and Disposal

After completion of the experimental protocol, rats were euthanized with100% CO2 followed by cervical dislocation. Rat carcasses were frozenuntil removal by The University of Queensland biological waste removalservice.

Data Analysis

Mean (±SEM) PPT versus time curves were plotted for each of the TestArticles, morphine and vehicle in FCA-rats. All data with n=2 wasgraphed as mean (±SD).

Statistical Analysis

The Mann-Whitney or Kruskall Wallis nonparametric tests, as implementedin the GraphPad Prism™ statistical analysis program (v3.0) were used tocompare (i) paw pressure thresholds before and after i.pl. FCA injection(ii) the effect of EMA compounds, morphine or vehicle on paw pressurethresholds after i.pl. FCA injection.

Example 3 Effects of EMA Compounds on Monoarthritis-Induced MechanicalHyperalgesia in Rats

Eighty rats were used. Three rats were excluded from the study becausethey were polyarthritic. The number of animals in the differentexperimental groups is mentioned below:

Vehicle: n=10

EMA300 (0.1 mg/kg): n=9

EMA300 (1 mg/kg): n=10

EMA300 (10 mg/kg): n=10

EMA400 (0.1 mg/kg): n=10

EMA400 (1 mg/kg): n=9

EMA400 (10 mg/kg): n=9

Morphine: n=10

Solubility issues were observed with EMA400 (PD-126,055) at 10 mg/kg butnot at 1 mg/kg and 0.1 mg/kg. No solubility issue was evidenced withEMA300 (PD-121,981). Morphine induced an antinociceptive effectcharacterized by a significant increase in the vocalization threshold ofmonoarthritic rats as compared to the pre-induction values (FIG. 7).

EMA300 induced a dose-dependent antihyperalgesic effect (+6%, +22% and+56% at 15 and 30 minutes after drug injection for the doses of 0.1, 1and 10 mg/kg, respectively) (FIG. 8).

EMA400 induced a significant antihyperalgesic effect 15 minutes afterthe injection of the 1 mg/kg dose (+20%). At 10 mg/kg, a significantantihyperalgesic effect was observed 15 minutes (+40%) and 30 minutesafter the injection (FIG. 9).

Conclusion

This study clearly shows that EMA300 and EMA400 induce antihyperalgesiceffects in a model of monoarthritis in rats. The lower effect of EMA400relative to EMA300 might be explained by some dissolution issues.

Materials and Methods Animals

80 male Sprague-Dawley rats (Charles River, France) weighing 180 g to200 g at the beginning of the experimental phase were included in thisstudy. They were housed in a temperature (19.5° C.-24.5° C.) andrelative humidity (45-65%) controlled room with a 12 h light/dark cycle,with ad libitum access to filtered tap-water and standard pelletedlaboratory chow (SAFE, France) throughout the study. Rats were housed 4per cage and a 7-day acclimatization period was observed before anytesting. Animals were individually identified on the tail. The study wasperformed according to the guidelines of the Committee for Research andEthical Issue of the I.A.S.P. (1983).

Test Articles

Test substances Salt/Base (name/code) Batch ratio Form Source EMA300Sm06-69 sodium salt powder GlycoSyn EMA400 Sm05-196-2.1.1 free powderGlycoSyn carboxylic acid

EMA300 (PD-121,981) was prepared as described in U.S. Pat. No.4,812,462. EMA400 (PD126,055) was prepared as described in InternationalPublication No. WO 93/23378. Both EMA300 and EMA400 were synthesized andsupplied by GlycoSyn, a business unit of Industrial Research Limited(New Zealand).

Study Materials Reference Substance

Reference substance Salt/Base (name/code) Batch ratio Form SourceMORPHINE D2893/9 1.13 powder COOPER

Vehicle

NaCl 0.9% (4151A101, B. BRAUN, France), DMSO (0503831, PROLABO, France).The vehicle was NaCl0.9%/DMSO (50/50)

Reagent

Freund's Complete Adjuvant (0640, DIFCO laboratories, USA).

Principal Equipment

Ugo Basile Analgesiometer (Ugo Basile, Italy) was used for the pawpressure test.

Principal Data Processing Systems

SigmaStat software was used for statistical analysis.

Experimental Design

# of Dose Group rats Compound (mg/kg) Route Volume 1 10 EMA300 0.1 ip 2mL/kg 2 10 EMA300 1 ip 2 mL/kg 3 10 EMA300 10 ip 2 mL/kg 4 10 EMA400 0.1ip 2 mL/kg 5 10 EMA400 1 ip 2 mL/kg 6 10 EMA400 10 ip 2 mL/kg 7 10Morphine 5 ip 2 mL/kg 8 10 Vehicle — ip 2 mL/kg

Experimental Procedure

Experimentation was done blindly using the block method withrandomization. Unilateral monoarthritis was induced by an intraarticularinjection of FCA (0.05 ml) into the tibio tarsial cavity of the righthindpaw of the rat under volatile anaesthetic (5% isofluorane). Fourteendays later, drugs were intraperitoneally given as a singleadministration. Pain reaction thresholds (vocalization or struggle) weremeasured using the paw pressure test before induction of monoarthritis,just before drug injections and 15 min, 30 min, 45 min, 1 h, 1 h 30, 2 hand 3 h after drug injections. Pressure was gradually applied to theinjected hindpaw of the rat (tibio tarsial articulation) and painreaction thresholds were determined as the pressure (g) required toelicit struggle or vocalization.

Data Presentation and Statistical Analyses

Results were expressed as pressure (g) which induces pain reaction(mean+/−SEM). The cut-off value corresponds to the maximum pressure thatthe apparatus allows (750 g). Data were analyzed by a two-way analysisof variance (ANOVA) to compare time-course scores. These analyses werefollowed by a Tukey test when the F-value was significant. Thesignificance level was p<0.05.

The disclosure of every patent, patent application, and publicationcited herein is hereby incorporated herein by reference in its entirety.

The citation of any reference herein should not be construed as anadmission that such reference is available as “Prior Art” to the instantapplication.

Throughout the specification the aim has been to describe the preferredembodiments of the invention without limiting the invention to any oneembodiment or specific collection of features. Those of skill in the artwill therefore appreciate that, in light of the instant disclosure,various modifications and changes can be made in the particularembodiments exemplified without departing from the scope of the presentinvention. All such modifications and changes are intended to beincluded within the scope of the appended claims.

What is claimed is:
 1. A method for the treatment or prophylaxis of aninflammatory pain in a subject, comprising administering to the subjectin need thereof an effective amount of an AT₂ receptor antagonist.
 2. Amethod according to claim 1, wherein the AT₂ receptor antagonist isselected from small molecules, nucleic acids, peptides, polypeptides andpeptidomimetics.
 3. A method according to claim 1, wherein the AT₂receptor antagonist is selected from compounds represented by theformula (I):

wherein: R¹ and R² are independently selected from H, benzyl,substituted benzyl, phenyl, substituted phenyl, C₁₋₆alkyl, substitutedC₁₋₆alkyl, C₃₋₆cycloalkyl, substituted C₃₋₆cycloalkyl, and heteroaryl,providing that both R¹ and R² are not hydrogen, R⁴ is selected from acarboxylate, carboxylic acid, sulfate, phosphate, sulfonamide,phosphonamide or amide, X is selected from CH, nitrogen, sulfur oroxygen with the proviso that when X is sulfur or oxygen one of R¹ or R²is absent, Y is selected from sulfur, oxygen or N—R^(N), where R^(N) isselected from H, C₁₋₆alkyl, substituted C₁₋₆alkyl, aryl, substitutedaryl, benzyl, substituted benzyl, C₁₋₄alkylaryl, substitutedC₁₋₄alkylaryl, OH, or NH₂, G is a five or six membered, homoaromatic orunsaturated, substituted or unsubstituted, heterocyclic ring includingbut not limited to the following rings systems:

where the symbol ‘*’ indicates the bond shared between the fused rings‘A’ and ‘G’, R⁵ is selected from H, C₁₋₆alkyl, phenyl, substitutedphenyl, substituted C₁₋₆alkyl, C₁₋₆alkoxy, or substituted C₁₋₆alkoxy, R⁶and R⁸ are independently selected from H, C₁₋₆alkyl, substitutedC₁₋₆alkyl, C₁₋₆alkoxy, substituted C₁₋₆alkoxy, phenyl, phenyloxy,benzyl, benzyloxy, benzylamino, biphenyl, substituted biphenyl,biphenyloxy, substituted biphenyloxy, naphthyl, substituted naphthyl,provided that one of R⁶ or R⁸ is not hydrogen, and R⁷ is selected fromphenyl, substituted phenyl, benzyl, substituted benzyl, biphenyl,substituted biphenyl, biphenylmethylene, substituted biphenylmethylene,naphthyl, substituted naphthyl, naphthylmethylene, and substitutednaphthylmethylene, or a pharmaceutically compatible salt thereof.
 4. Amethod according to claim 1, wherein the AT₂ receptor antagonist isselected from compounds represented by the formula (II):

wherein: R¹ and R² are independently selected from H, phenyl,substituted phenyl, benzyl, substituted benzyl, C₁₋₆alkyl, substitutedC₁₋₆alkyl, C₃₋₆cyloalkyl, substituted C₃₋₆cycloalkyl, heteroaryl, andsubstituted heteroaryl, substituted biphenylmethylene and saturated andunsaturated substituted biphenylmethylene, provided that one of R¹ or R²is not hydrogen, R⁴ is selected from a carboxylate, carboxylic acid,sulfate, phosphate, sulfonamide, phosphonamide or amide, X is selectedfrom CH, nitrogen, sulfur or oxygen with the proviso that when X issulfur or oxygen one of R¹ or R² is absent, and Y is selected fromsulfur, oxygen or N—R^(N), where R^(N) is selected from H, C₁₋₆alkyl,substituted C₁₋₆alkyl, aryl, substituted aryl, benzyl, substitutedbenzyl, C₁₋₄alkylaryl, substituted C₁₋₄alkylaryl, OH, or NH₂, or apharmaceutically compatible salt thereof.
 5. A method according to claim1, wherein the AT₂ receptor antagonist is selected from compoundsrepresented by the formula (III):

wherein: R¹, R² and R³ are independently selected from H, phenyl,substituted phenyl, benzyl, substituted benzyl, C₁₋₆alkyl, substitutedC₁₋₆alkyl, with the proviso that at least one of R¹ or R² are nothydrogen, X is selected from CH, nitrogen, sulfur or oxygen with theproviso that when X is sulfur or oxygen, one of R¹ or R² is absent, oris aryl or heteroaryl with the proviso that both R¹ and R² are absent, Vis selected from CH or nitrogen atom, Y is selected from sulfur, oxygenor N—R^(N), where R^(N) is selected from H, C₁₋₆alkyl, substitutedC₁₋₆alkyl, aryl, substituted aryl, benzyl, substituted benzyl,C₁₋₄alkylaryl, substituted C₁₋₄alkylaryl, OH, or NH₂, R⁴ is selectedfrom a carboxylate, carboxylic acid, sulfate, phosphate, sulfonamide,phosphonamide, or amide, G is a five or six membered, homoaromatic orunsaturated, substituted or unsubstituted, heterocyclic ring includingbut not limited to the following rings systems:

where the symbol ‘*’ indicates the bond shared between the fused rings‘A’ and ‘G’, R⁵ is selected from H, C₁₋₆alkyl, phenyl, substitutedphenyl, substituted C₁₋₆alkyl, or C₁₋₆alkoxy, R⁶ and R⁸ areindependently selected from H, C₁₋₆alkyl, substituted C₁₋₆alkyl,C₁₋₆alkoxy, substituted C₁₋₆alkoxy, phenyl, phenyloxy, benzyl,benzyloxy, benzylamino, biphenyl, substituted biphenyl, biphenyloxy,substituted biphenyloxy, naphthyl, substituted naphthyl, provided thatone of R⁶ or R⁸ is not hydrogen, and R⁷ is selected from phenyl,substituted phenyl, benzyl, substituted benzyl, biphenyl, substitutedbiphenyl, biphenylmethylene, substituted biphenylmethylene, naphthyl,substituted naphthyl, naphthylmethylene, and substitutednaphthylmethylene, or a pharmaceutically compatible salt thereof.
 6. Amethod according to claim 1, wherein the AT₂ receptor antagonist isselected from compounds represented by the formula (IV):

wherein: R¹⁰ is selected from H, halogen, C₁₋₆alkyl, phenyl, substitutedphenyl, substituted C₁₋₆alkyl, or C₁₋₆alkoxy, R⁹ is selected from—NR¹³R¹⁴, wherein R¹³ and R¹⁴ are independently selected from C₁₋₆alkyl,substituted C₁₋₆alkyl, aryl, substituted aryl, benzyl, substitutedbenzyl, C₁₋₄alkylaryl, substituted C₁₋₄alkylaryl, OH, or NH₂; a five orsix membered, saturated or unsaturated, substituted or unsubstituted,carbocyclic or heterocyclic ring including but not limited to:

V is selected from CH or a nitrogen atom, Y is selected from sulfur,oxygen or N—R^(N), where R^(N) is selected from H, C₁₋₆alkyl,substituted C₁₋₆alkyl, aryl, substituted aryl, benzyl, substitutedbenzyl, C₁₋₄alkylaryl, substituted C₁₋₄alkylaryl, OH, or NH₂, G is afive or six membered homoaromatic or heterocyclic, unsaturated,substituted ring including but not limited to the following ringssystems:

where the symbol ‘*’ indicates the bond shared between the fused rings‘A’ and ‘G’, R⁵ is selected from C₁₋₆alkyl, phenyl, substituted phenyl,substituted C₁₋₆alkyl, or C₁₋₆alkoxy, R⁶ and R⁸ are independentlyselected from H, C₁₋₆alkyl, substituted C₁₋₆alkyl, C₁₋₆alkoxy,substituted C₁₋₆alkoxy, phenyl, phenyloxy, benzyl, benzyloxy,benzylamino, biphenyl, substituted biphenyl, biphenyloxy, substitutedbiphenyloxy, naphthyl, substituted naphthyl, provided that one of R⁶ orR⁸ is not hydrogen, and R⁷ is selected from phenyl, substituted phenyl,benzyl, substituted benzyl, biphenyl, substituted biphenyl,biphenylmethylene, substituted biphenylmethylene, naphthyl, substitutednaphthyl, naphthylmethylene, and substituted naphthylmethylene, or apharmaceutically compatible salt thereof.
 7. A method according to claim1, wherein the AT₂ receptor antagonist is selected from compoundsrepresented by the formula (V):

wherein: M is H or a halogen (fluoro, bromo, iodo, chloro), R⁵ isselected from C₁₋₆alkyl, phenyl, substituted phenyl, substitutedC₁₋₆alkyl, or C₁₋₆alkoxy, R¹⁶ is selected from C₁₋₆alkylamino,C₁₋₆dialkylamino, substituted C₁₋₆alkylamino, substitutedC₁₋₆dialkylamino, arylamino, diarylamino, substituted arylamino,substituted diarylamino, alkylarylamino, dialkylarylamino, substitutedalkylarylamino, substituted dialkylarylamino, heteroarylamino,substituted heteroarylamino, cycloalkylamino, dicycloalkylamino,diheteroarylamino, alkylcarbonylamino, arylcarbonylamino,alkylarylcarbonylamino, cycloalkylcarbonylamino, and R¹⁷ is selectedfrom C₁₋₆alkyl, substituted C₁₋₆alkyl, phenyl, substituted phenyl,benzyl, substituted benzyl, biphenyl, substituted biphenyl,biphenylmethylene, substituted biphenylmethylene, naphthyl, substitutednaphthyl, heteroaryl, or substituted heteroaryl, or a pharmaceuticallycompatible salt thereof.
 8. A method according to claim 1, wherein theAT₂ receptor antagonist is selected from peptide compounds representedby the formula (VIII):R₁-R₂-R₃-R₄-R₅-R₆-Pro-R₇  (VIII) wherein: R₁ is absent or is selectedfrom hydrogen, succinyl, L-aspartyl, sarcosyl, L-seryl, succinamyl,L-propyl, glycyl, L-tyrosyl, N_(α)-nicotinoyl-tyrosyl, or D- orL-asparagyl; R₂ is selected from arginyl or N-benzoylcarbonyl arginyl;R₃ is absent or valyl; R₄ is absent or is selected from L-phenylalanylor L-tyrosyl; R₅ is selected from valyl, L-isoleucyl, L-alanyl orL-lysyl; R₆ is selected from L-histidyl, L-isoleucyl, L-tyrosyl orp-aminophenylalanyl; and R₇ is selected from L-alanine, L-tyrosine, L-or D-leucine, glycine, L-isoleucine or □-alanine residue; or apharmaceutically compatible salt thereof.
 9. A method according to claim3, wherein the AT₂ receptor antagonist is selected from compounds, orpharmaceutically compatible salts thereof, represented by the formula(IX):

wherein: X is selected from CH or nitrogen, R¹ and R² are independentlyselected from phenyl, substituted phenyl, benzyl, substituted benzyl,C₁₋₆alkyl, substituted C₁₋₆alkyl, C₃₋₆cycloalkyl, substitutedC₃₋₆cycloalkyl and heteroaryl, R⁵ is selected from hydrogen, C₁₋₆alkyl,phenyl, substituted phenyl, substituted C₁₋₆alkyl, C₁₋₆alkoxy, andsubstituted C₁₋₆alkoxy, and R⁷ is selected from is selected from phenyl,substituted phenyl, benzyl, substituted benzyl, biphenyl, substitutedbiphenyl, biphenylmethylene, substituted biphenylmethylene, naphthyl,substituted naphthyl, naphthylmethylene, and substitutednaphthylmethylene.
 10. A method according to claim 3, wherein the AT₂receptor antagonist is selected from compounds, or pharmaceuticallycompatible salts thereof, represented by the formula (X):

wherein: X is selected from CH or nitrogen, R¹ and R² are independentlyselected from phenyl, substituted phenyl, benzyl, substituted benzyl,C₁₋₆alkyl, substituted C₁₋₆alkyl, C₃₋₆cycloalkyl, substitutedC₃₋₆cycloalkyl and heteroaryl, and R⁶ and R⁸ are independently selectedfrom H, C₁₋₆alkyl, substituted C₁₋₆alkyl, C₁₋₆alkoxy, substitutedC₁₋₆alkoxy, phenyl, phenyloxy, benzyl, benzyloxy, benzylamino, biphenyl,substituted biphenyl, biphenyloxy, substituted biphenyloxy, naphthyl,substituted naphthyl, provided that one of R⁶ or R⁸ is not hydrogen. 11.A method according to claim 4, wherein the AT₂ receptor antagonist isselected from compounds, or pharmaceutically compatible salts thereof,represented by the formula (II), wherein R¹ and R² are independentlyselected from phenyl or substituted phenyl, C₁₋₆alkyl, substitutedbiphenylmethylene, X is selected from CH or nitrogen and R⁴ is acarboxylic acid.
 12. A method according to claim 6, wherein the AT₂receptor antagonist is selected from compounds, or pharmaceuticallycompatible salts thereof, represented by the formula (XI):

wherein: V is selected from CH or a nitrogen atom, Y and W areindependently selected from sulfur, oxygen or N—R^(N), where R^(N) isselected from H, C₁₋₆alkyl, substituted C₁₋₆alkyl, aryl, substitutedaryl, benzyl, substituted benzyl, C₁₋₄alkylaryl, substitutedC₁₋₄alkylaryl, OH, or NH₂, R⁵ is selected from C₁₋₆alkyl, phenyl,substituted phenyl, substituted C₁₋₆alkyl, or C₁₋₆alkoxy, R⁷ is selectedfrom phenyl, substituted phenyl, benzyl, substituted benzyl, biphenyl,substituted biphenyl, biphenylmethylene, substituted biphenylmethylene,naphthyl, substituted naphthyl, naphthylmethylene, and substitutednapthylmethylene naphthylmethylene, R⁹ is selected from —NR¹³R¹⁴,wherein R¹³ and R¹⁴ are independently selected from C₁₋₆alkyl,substituted C₁₋₆alkyl, aryl, substituted aryl, benzyl, substitutedbenzyl, C₁₋₄alkylaryl, substituted C₁₋₄alkylaryl, OH, or NH₂; a five orsix membered, saturated or unsaturated, substituted or unsubstituted,carbocyclic or heterocyclic ring including but not limited to:

and R¹⁰ is selected from H, halogen, C₁₋₆alkyl, phenyl, substitutedphenyl, substituted C₁₋₆alkyl, or C₁₋₆alkoxy.
 13. A method according toclaim 9, wherein the AT₂receptor antagonist is selected from compounds,or pharmaceutically compatible salts thereof, represented by the formula(IX), wherein R¹ and R² are phenyl, X is CH, R⁵ is hydrogen orC₁₋₄alkyl, and R⁷ is selected from substituted benzyl.
 14. A methodaccording to claim 39, wherein the AT₂ receptor antagonist is selectedfrom compounds, or pharmaceutically compatible salts thereof,represented by the formula (IX), R⁵ is hydrogen and R⁷ is selected from4-(N,N-dimethylamino)-3-methylbenzyl, 4-methoxy-3-methylbenzyl,4-amino-3-methylbenzyl.
 15. A method according to claim 10, wherein theAT₂ receptor antagonist is selected from compounds, or pharmaceuticallycompatible salts thereof, represented by the formula (X), wherein R¹ andR² are independently selected from phenyl or substituted phenyl, X isCH, R⁴ is a carboxylic acid, R⁶ is selected from C₁₋₆alkyl, substitutedC₁₋₆alkyl, C₁₋₆alkoxy, substituted C₁₋₆alkoxy, phenyl, phenyloxy, and R⁸is selected from H, phenyl, phenyloxy, benzyl, benzyloxy, benzylamino,biphenyl, substituted biphenyl, biphenyloxy, substituted biphenyloxy,naphthyl, and substituted naphthyl.
 16. A method according to claim 12,wherein the AT₂ receptor antagonist is selected from compounds, orpharmaceutically compatible salts thereof, represented by the formula(XI) wherein V is CH, Y and W are oxygen, R⁵ is selected from C₁₋₆alkyl,phenyl, substituted phenyl, substituted C₁₋₆alkyl, or C₁₋₆alkoxy, R⁷ isselected from biphenyl, substituted biphenyl, biphenylmethylene,substituted biphenylmethylene, naphthyl, substituted naphthyl,naphthylmethylene, and substituted naphthylmethylene, R^(N) is selectedfrom H, C₁₋₆alkyl, substituted C₁₋₆alkyl, aryl, substituted aryl,C₁₋₄alkylaryl, substituted C₁₋₄alkylaryl, OH, or NH₂, R⁹ is selectedfrom —NR¹³R¹⁴, wherein R¹³ and R¹⁴ are independently selected fromC₁₋₆alkyl, substituted C₁₋₆alkyl, aryl, substituted aryl, benzyl,substituted benzyl, C₁₋₄alkylaryl, substituted C₁₋₄alkylaryl, OH, orNH₂; a five or six membered, saturated or unsaturated, substituted orunsubstituted, carbocyclic or heterocyclic ring including but notlimited to:

and R¹⁰ is selected from H, halogen, C₁₋₆alkyl, phenyl, substitutedphenyl, substituted C₁₋₆alkyl, or C₁₋₆alkoxy.
 17. A method according toclaim 12, wherein the AT₂ receptor antagonist is selected fromcompounds, or pharmaceutically compatible salts thereof, represented bythe formula (XI) wherein V is CH, Y and W are oxygen, R⁵ is selectedfrom C₁₋₆alkyl, substituted C₁₋₆alkyl, or C₁₋₆alkoxy, R⁷ is selectedfrom biphenylmethylene, substituted biphenylmethylene,naphthylmethylene, and substituted naphthylmethylene, R^(N) is selectedfrom H, C₁₋₆alkyl, substituted C₁₋₆alkyl, aryl, substituted aryl,C₁₋₄alkylaryl, substituted C₁₋₄alkylaryl, R⁹ is selected from —NR¹³R¹⁴,wherein R¹³ and R¹⁴ are independently selected from C₁₋₆alkyl,substituted C₁₋₆alkyl, aryl, substituted aryl, benzyl, substitutedbenzyl, C₁₋₄alkylaryl, substituted C₁₋₄alkylaryl; a five or sixmembered, saturated or unsaturated, substituted or unsubstituted,carbocyclic or heterocyclic ring including but not limited to:

and R¹⁹ is H.
 18. A method according to claim 12, wherein the AT₂receptor antagonist is selected from compounds, or pharmaceuticallycompatible salts thereof, represented by the formula (XI) wherein R⁷ isselected from a substituted biphenylmethylene group represented byformula (XII):

wherein: R^(H) is selected from hydrogen, —OH, —SH, —HN₂, nitrile, CF₃,halo (F, Cl, Br, I), —NO₂, C₁-C₄alkylamino, C₁-C₄dialkylamino, and R^(A)is selected from C₁-C₁₀alkyl, C₃-C₁₀alkenyl, C₃-C₁₀alkynyl, aryl,—(C₁-C₄alkyl)aryl, heterocyclyl, heteroaryl, C₃-C₇-cycloalkyl,C₁-C₄-perfluoroalkyl, —OH, —SH, —HN₂, nitrile, C₁-C₁₀-alkoxy,haloC₁₋₄alkyl, hydroxyC₁₋₄alkyl, C₁-C₁₀-alkylthio, —CF₃, halo (F, Cl,Br, I), —NO₂, —CO₂R²³, —NH₂, C₁-C₄alkylamino, C₁-C₄dialkylamino,arylamino, diarylamino, arylC₁₋₄alkylamino, arylC₁₋₄dialkylamino,aryloxy, arylC₁₋₄alkyloxy, formyl, C₁₋₁₀alkylcarbonyl andC₁₋₁₀alkoxycarbonyl, —PO₃H₂, —CO₂H, —CONHSO₂R²¹, —CONHSO₂NHR²⁰,—NHCONHSO₂R²¹, —NHSO₂R²¹, —NHSO₂NHCOR²¹, —SO₂NHR²⁰, —SO₂NHCOR²¹,—SO₂NHCONHR²⁰, —SO₂NHCO₂R²¹, tetrazolyl, —CHO, —CONH₂, —NHCHO,—CO—(C₁-C₆perfluoroalkyl), —S(O)_(r)—(C₁-C₆ perfluoroalkyl), wherein R²⁰is H, C₁-C₅-alkyl, aryl, —(C₁-C₄-alkyl)-aryl, heteroaryl; R²¹ is aryl,C₃-C₇-cycloalkyl, C₁-C₄-perfluoroalkyl, C₁-C₄alkyl, optionallysubstituted with a substituent selected from the group consisting ofaryl, heteroaryl, —OH, —SH, C₁-C₄-alkyl, C₁-C₄alkoxy, C₁-C₄alkylthio,—CF₃, halo, —NO₂, —CO₂R²³, —NH₂, C₁-C₄-alkylamino, C₁-C₄-dialkylamino,—PO₃H₂, or heteroaryl; and R²² is selected from C₁-C₆-alkyl,C₃-C₆-cycloalkyl, aryl, —(C₁-C₅-alkyl)-aryl, or heteroaryl.
 19. A methodaccording to claim 1, wherein the AT₂ receptor antagonist is anantigen-binding molecule that is immuno-interactive with an AT₂ receptorpolypeptide.
 20. A method according to claim 1, wherein the AT₂ receptorantagonist is a nucleic acid molecules that inhibits or otherwisereduces the level or functional activity of an expression product of anAT₂ gene.
 21. A method according to claim 20, wherein the AT₂ receptorantagonist is an antisense molecule.
 22. A method according to claim 20,wherein the AT₂ receptor antagonist is a ribozyme.
 23. A methodaccording to claim 20, wherein the AT₂ receptor antagonist is an RNAimolecule.
 24. A method according to claim 1, wherein the AT₂ receptorantagonist is administered in the form of a composition comprising apharmaceutically acceptable carrier or diluent.
 25. A method accordingto claim 24, wherein the composition is administered by a route selectedfrom injection, topical application or the oral route, over a period oftime and in an amount, which is effective to treat or prevent theinflammatory pain.
 26. A method according to claim 1, wherein theinflammatory pain results from an infection.
 27. A method according toclaim 26, wherein the infection is selected from a viral, bacterial orfungal infection.
 28. A method according to claim 1, wherein theinflammatory pain results from a tissue burn.
 29. A method according toclaim 28, wherein the tissue burn is selected from a burn of thecutaneous tissue and a sunburn.
 30. A method according to claim 1,wherein the inflammatory pain results from an autoimmune disease.
 31. Amethod according to claim 30, wherein the autoimmune disease is selectedfrom rheumatoid arthritis, inflammatory arthritis, psoriasis, ankylosingspondylitis, osteoarthritis, colitis and irritable bowel disease.
 32. Amethod according to claim 1, wherein the inflammatory pain results froman inflammatory condition of a tissue or organ selected from skin,muscle, and joints.
 33. A method according to claim 1, wherein theinflammatory pain results from a cancer.
 34. A method according to claim1, wherein the inflammatory pain results from a traumatic injury orsurgery.
 35. A method for preventing or attenuating inflammatory pain ina subject, comprising administering to the subject an effective amountof an AT₂ receptor antagonist, which is optionally in the form of acomposition comprising a pharmaceutically acceptable carrier and/ordiluent.
 36. A method for producing analgesia in a subject having, or atrisk of developing, a inflammatory pain, comprising administering to thesubject an effective amount of an AT₂ receptor antagonist, which isoptionally in the form of a composition comprising a pharmaceuticallyacceptable carrier and/or diluent.
 37. A method for identifying agentsthat antagonize an AT₂ receptor for treatment of inflammatory pain,comprising contacting a preparation with a test agent, wherein thepreparation comprises (i) a polypeptide comprising an amino acidsequence corresponding to at least a biologically active fragment of anAT₂ receptor polypeptide, or to a variant or derivative thereof; or (ii)a polynucleotide that comprises at least a portion of a genetic sequencethat regulates the expression of a gene that encodes an AT₂ receptorpolypeptide, wherein the polynucleotide is operably linked to a reportergene and detecting a decrease in the level or functional activity of theAT₂ receptor polypeptide, or an expression product of the reporter gene,relative to a normal or reference level or functional activity in theabsence of the test agent, which indicates that the agent is an AT₂receptor antagonist and is useful for the treatment of inflammatorypain.
 38. A method according to claim 38, comprising contacting a firstsample of cells expressing an AT₂ receptor with an AT₂ receptor ligandand measuring a marker; contacting a second sample of cells expressingthe AT₂ receptor with an agent and the ligand, and measuring the marker;and comparing the marker of the first sample of cells with the marker ofthe second sample of cells.
 39. A method according to claim 38,comprising measuring the levels of one or more markers, or combinationsof markers associated with the activation of the AT₂ receptor or withthe proliferation or differentiation of the cells.
 40. A methodaccording to claim 36, wherein the marker or markers is/are selectedfrom Zfhep expression, nitric oxide levels or nitric oxide synthaselevels.
 41. A method according to claim 36, wherein the marker ormarkers is/are selected from Zfhep expression, nitric oxide levels ornitric oxide synthase levels, and the agent tests positive if itinhibits or otherwise reduces any one or more of Zfhep expression or thelevel of nitric oxide or the level or functional activity of nitricoxide synthase or the differentiation of the cells.
 42. A method ofproducing an agent for producing analgesia in a subject having, or atrisk of developing, inflammatory pain, comprising testing an agentsuspected of antagonizing an AT₂ receptor according to claim 38; andsynthesizing the agent on the basis that it tests positive for theantagonism.
 43. A method according to claim 43, further comprisingderivatising the agent, and optionally formulating the derivatized agentwith a pharmaceutically acceptable carrier or diluent, to improve theefficacy of the agent for treating or preventing inflammatory pain. 44.A method according to claim 3 wherein the compound of formula (I) isselected from:2-(Diphenylacetyl)-5-benzyloxy-6-methoxy-1,2,3,4-tetrahydroisoquinoline-3-carboxylicacid (PD-126055) or an enantiomer thereof;S(+)-1-[[4-(Dimethylamino)-3-methylphenyl]methyl]-5-(diphenylacetyl)-4,5,6,7-tetrahydro-1H-imidazo-[4,5-c]pyridine-6-carboxylicacid (PD-123,319); andS(+)-1-[[4-hydroxy-3-methylphenyl]methyl]-5-(diphenylacetyl)-4,5,6,7-tetrahydro-1H-imidazo-[4,5-c]pyridine-6-carboxylicacid (PD-121,981).
 45. A method according to claim 45 wherein the AT₂receptor antagonist is2-(Diphenylacetyl)-5-benzyloxy-6-methoxy-1,2,3,4-tetrahydroisoquinoline-3-carboxylicacid (PD-126055) or an enantiomer thereof.